Patent Application
20230054789
Battery packs may be used with different types of equipment, including outdoor power equipment, vehicles, aerial man lifts, floor care devices, golf carts, lift trucks and other industrial vehicles, floor care devices, recreational utility vehicles, industrial utility vehicles, lawn and garden equipment, energy storage or battery backup systems, and other electric vehicles. Outdoor power equipment includes lawn mowers, riding tractors, snow throwers, pressure washers, generators, tillers, log splitters, zero-turn radius mowers, walk-behind mowers, riding mowers, pavement surface preparation devices, industrial vehicles such as forklifts, utility vehicles, commercial turf equipment such as blowers, vacuums, debris loaders, overseeders, power rakes, aerators, sod cutters, brush mowers, sprayers, spreaders, etc. Outdoor power equipment may, for example, use one or more electric motors to drive an implement, such as a rotary blade of a lawn mower, a pump of a pressure washer, the auger of a snow thrower, the alternator of a generator, and/or a drivetrain of the outdoor power equipment. An electric vehicle may also be other types of vehicles such as cars, trucks, automobiles, motorcycles, scooters, boats, all-terrain vehicles (ATVs), personal water craft, snowmobiles, utility vehicles (UTVs), other off-road vehicles (ORVs) and the like.
One exemplary embodiment relates to a battery pack. The battery pack includes a housing, a positive terminal, a negative terminal, and cell module assemblies (CMAs). The housing includes a first compartment and a second compartment. The positive terminal and the negative terminal are each externally accessible from the housing and extend into the first compartment. The CMAs are received within the second compartment, and are electrically coupled to the positive terminal and the negative terminal through a connection extending from the second compartment into the first compartment. The CMAs each include a plurality of rechargeable lithium-ion battery cells. The first compartment is accessible through a first panel that is movable coupled to the housing through a first securing mechanism providing a first level of access. The second compartment is accessible through a second panel that is movable coupled to the housing through a second securing mechanism providing a second level of access. The second securing mechanism is different from the first securing mechanism, and includes a lock.
Another exemplary embodiment relates to a battery pack. The battery pack includes a housing, a positive terminal, a negative terminal, and CMAs. The housing includes a first compartment and a second compartment. The positive terminal and the negative terminal are each externally accessible from the housing and extend into the first compartment. The CMAs are received within the second compartment, and are electrically coupled to the positive terminal and the negative terminal through a connection extending from the second compartment into the first compartment. The CMAs each include a plurality of rechargeable lithium-ion battery cells. The first compartment is accessible through a first panel that is movable coupled to the housing through a first securing mechanism providing a first level of access. The second compartment is accessible through a second panel that is movably coupled to the housing through a second securing mechanism providing a second level of access. The second level of access is lower (e.g., less accessible) than the first level of access.
Another exemplary embodiment relates to a battery pack. The battery pack includes a housing, a positive terminal, a negative terminal, a data connector terminal, and CMAs. The positive terminal, negative terminal, and data connector terminal are each externally accessible from the housing and extend into the first compartment. The CMAs are received within the second compartment, and are electrically coupled to the positive terminal and the negative terminal through a physical connection extending from the second compartment into the first compartment. The CMAs each include a plurality of rechargeable lithium-ion battery cells. A battery management system is positioned within the housing and is coupled to the data connector terminal. The battery management system is configured to communicate externally through the data connector terminal (e.g., to provide performance data, operational parameters, etc. from the CMAs to an external device). The first compartment is accessible through a first securing mechanism providing a first level of access. The second compartment is accessible through a second securing mechanism providing a second level of access. The second level of access is lower (e.g., more difficult to access) than the first level of access.
This summary is illustrative only and is not intended to be in any way limiting. Other aspects, inventive features, and advantages of the devices or processes described herein will become apparent in the detailed description set forth herein, taken in conjunction with the accompanying figures, wherein like reference numerals refer to like elements.
The disclosure will become more fully understood from the following detailed description, taken in conjunction with the accompanying figures.
Before turning to the figures, which illustrate the exemplary embodiments in detail, it should be understood that the present application is not limited to the details or methodology set forth in the description or illustrated in the figures. It should also be understood that the terminology is for the purpose of description only and should not be regarded as limiting.
Referring to
Referring to
The battery pack 100 may include multiple cell module assemblies (CMAs) 270 vertically positioned in tiers, where a first tier of CMAs 270 is positioned directly above a second tier of CMAs 270. Each CMA 270 includes a top CMA cell holder frame (e.g., top CMA cell holder frame 702 (
In some embodiments, the battery pack 100 is assembled such that there are gaps between the battery cells of each CMA 270 and a plate. These gaps between the battery cells 202 of the CMAs 270 and the plates in each tier of the battery pack 100 may prevent damage to the battery pack 100 during thermal events. For example, the gaps between the cells of the CMAs 270 and the plates (e.g., top plate 218, midplates 210) allow ejected material from a bad battery cell to build up above the bad battery cell instead of the material extending sideways to the other battery cells 202 in the CMA. Beneficially, when heat is dissipated from the bad battery cell, the likelihood of the thermal event cascading to the other battery cells 202 and causing more damage to the components of the battery pack 100 is reduced. A catastrophic chain reaction from one bad battery cell igniting neighboring battery cells (e.g., battery cells above or below a run-away battery cell) and propagating through short circuit to other battery cells 202 is a potential source of failure. As such, the plates between the positive side of battery cells 202 in the CMAs 270 and the adjacent plates help prevent run-away battery cells from propagating the run-away event and potentially leading to the failure of battery pack 100.
Each of the plates in the battery pack 100 can be electrically isolated to allow each tier of the battery pack 100 to be disconnected while servicing an individual CMA 270 of the battery pack 100. In some embodiments, each CMA 270 of the battery pack 100 can be replaced with removable fasteners and common service tools, such as wrenches and screwdrivers. In some embodiments, each tier of the battery pack 100 is electrically disconnected from the rest of the battery pack 100 until the final assembly of the battery pack is completed and the end wires are connected. The ability to isolate a CMA 270 requiring service due to one or more bad battery cells can advantageously improve the health and battery life of the overall battery pack 100.
The mounting hardware 268 may include fasteners that are easily serviceable with tools such as wrenches. In addition to the mounting hardware 268 used throughout the battery pack 100 providing structure and stability for the battery pack 100, the mounting hardware 268 may provide thermal conductivity along all structural components, plates, spacers, etc. of the battery pack 100. The spacers 209 between all of the tiers of the battery pack 100 may include compression limiters 208. The compression limiters 208 may be steel or aluminum and provide a thermally conductive path, while still maintaining electrically independent tiers, through the tiers of the battery pack 100. For example, the compression limiters 208 may route heat throughout the battery pack 100. In some embodiments, each compression limiter 208 of a spacer 209 has a unique serial number.
A thermistor 217 may be coupled to one of the battery cells 202 within a CMA 270 of the battery pack 100. In some embodiments, the thermistor 217 is secured to a battery cell 202 with tape 216. In some embodiments, closed cell foam adhesive is used to mount the thermistors 217 to the battery cells 202. Each CMA 270 within the battery pack 100 includes one thermistor 217 to monitor the temperature of that individual CMA. The battery pack 100 may also include a resistive heating strip on the plates for uniformly heating the battery pack 100. In some embodiments, each tier has a resistive heating strip that runs at a different heating capacity than the heating strips on the other tiers. The heating element's resistance may change based upon its own temperature. For example, the variable resistance of the heating elements may be based on the temperature of the heating element. As such, when a certain area of the battery pack 100 is determined to be at a higher temperature than the rest of the battery pack 100 (e.g., the top tier of the battery pack is near a component of outdoor power equipment that produces a lot of external heat), the resistive heating element near that area may have a lower heating level than other resistive heating elements in the battery pack 100. For example, the top tier of the battery pack 100 may have a resistive heating element at a lower wattage than a resistive heating element on a lower tier, such as the bottom tier of the battery pack 100.
In other embodiments, a tier of the battery pack 100 may include more resistive heating elements than a different tier. In some embodiments, the resistive heating elements may have positive or negative coefficients to increase the capability of the battery pack 100 to be thermally self-regulated. The battery pack 100 may receive external power to run the internal pack heating elements (e.g., the resistive heating strips) from a charger, or another energy source, using the existing, external terminals. As such, the temperature of the battery pack 100 may be increased above a threshold temperature level without any current flowing into or out of the battery pack 100 and the battery cells 202. In some embodiments, an internal circulating fan helps create a uniform internal temperature for the battery pack 100 without exchanging air outside of the housing 108 of the battery pack 100. Advantageously, by creating a more uniform temperature level inside the housing 108, the battery pack 100 may avoid a particular area of the battery pack 100 having a much higher temperature than the other components of the battery pack 100.
Each CMA 270 of the battery pack 100 includes multiple battery cells 202, which can together output power to operate a vehicle or other equipment, such as various outdoor power equipment. In some embodiments, the battery cells 202 are lithium-ion battery cells. The battery cells 202 can be lithium-ion battery cells rated at 3.6 volts and 3 amp-hours, for example. As illustrated, each of the fourteen CMAs 270 include thirty-two battery cells 202 arranged in four rows of eight cells each, which can be seen in greater detail in
The battery pack 100 also includes a battery management system (BMS) 222 for regulating the currents and/or voltages involved in the charging and discharging processes in order to ensure that the battery cells 202 are not damaged or otherwise brought to problematic charge states. For example, the BMS 222 may block an electrical current from being delivered to the battery cells 202, or may block a current being drawn from the battery cells 202 based the current and voltage properties of the signal and/or of the CMA 270. The BMS 222 may also implement controls based on a temperature as detected by a temperature sensor (e.g., thermistor 217) and regulate operation of the CMAs 270 based on over temperature or under temperature conditions determined by the detected temperature received. Additionally, the BMS 222 may allow operation with a battery pack having a variable power supply. The battery pack 100 can be connected in series or parallel because of the protected BMS 222 within the battery pack 100. In some embodiments, the same BMS 222 may be used with a battery pack 100 that has a nominal voltage (V) of 24V, 36V, or 48V.
In some embodiments, a dual controller area network (CAN) bus data communication line is included in the battery pack 100 and electrically and communicatively coupled to the BMS 222, enabling vehicle and/or machine functionality. The two baud rates of the dual CAN bus line may allow the battery pack 100 to act as a gateway (e.g., an Internet of Things (IoT) gateway) between the vehicle (e.g., outdoor power equipment) and the dual CAN bus line in the battery. In some embodiments, an IoT gateway is also included in the battery pack 100 (e.g., integrated with the BMS 222), rather than external to the battery pack 100. The dual CAN bus line may implement IoT in the battery pack 100 to use as an IoT module for the vehicle (e.g., outdoor power equipment).
The maximum charge capacity of the battery cells 202 of the CMAs 270 in the battery pack 100 decay over the life of the battery pack 100 as the battery pack 100 ages. This decay is caused by the battery pack 100 being cycled by discharging and then recharging the battery pack 100, changes in temperature (e.g., high temperatures), and degradation of the chemistry of the battery cells 202. A cycle is the transition from the battery pack's fully charged state (as allowed by the BMS 222) to a partially or fully discharged state (as allowed by the BMS 222). As the number of cycles increases over the life of the battery pack 100, the battery pack 100's maximum charge capacity declines.
The BMS 222 of the battery pack 100 may include an integrated data logger and may be programmed to store data related to the operation of the CMAs 270 in a memory of the BMS 222. The information recorded by the BMS 222 may then be used to determine a useful life measurement for each CMA. The useful life measurement may be expressed in terms of a percentage of life (e.g., the CMA 270 is at 100% life when brand new). The useful life measurement may be used to set multiple end of life thresholds tied to certain applications for the CMAs 270. For example, a CMA's first life could extend between 100% and 70% charge capacity where the CMA 270 would be suitable for use powering outdoor power equipment (e.g., a commercial lawn mower). After the end of the first life (e.g., a useful life measurement below 70%), a CMA 270 may be reconditioned and put to use in its second life (e.g., between 70% and 50%), in which the CMA 270 is suitable for use in a battery pack for equipment having lower energy requirements than the equipment powered by the CMA 270 during its first life in battery pack 100. In some embodiments, the programming of the BMS 222 of the battery pack 100 being used in a second life is reset or reconfigured. By resetting the programming of the BMS 222 at the beginning of the battery pack 100's second life, the BMS 222 may show a charge capacity of 100% relative to its new lowered charge capacity. For example, the BMS 222 may include an “odometer” like measurement that is reset such that a 5 kilowatt-hour (kW-hr) battery pack with a charge capacity of 80% is now a 4 kW-hr battery pack with a charge capacity at 100%.
The useful life measurement can be determined by a number of data points indicative of useful life that can be monitored and saved by BMS 222. These useful life indicators include charge capacity, days, or other time elapsed since a commissioning date when each CMA 270 is first put into service, number of cycles since the commissioning date, depth of cycle for individual cycles or groups of cycles, an electrical charge meter that counts the number of coulombs supplied by the CMAs 270 since the commission date, an event counter of operation of the CMAs 270 in extreme temperature conditions (e.g., above 140 degrees Fahrenheit) for individual events or groups of events, the current supplied by the CMAs 270, the current received by the CMAs 270 for charging, the voltage supplied by the CMAs 270, and/or the voltage applied to the CMAs 270 during charging. In other embodiments, different combinations of useful life indicators are monitored and saved by the BMS 222. The useful life indicators identified above may be monitored individually in some embodiments or monitored in any combination in other embodiments. In other embodiments, useful life indicators are tracked and stored for each individual battery cell 202 of each CMA 270 in the battery pack 100 in the integrated memory of the BMS 222.
Gathering and tracking useful life indicators across the life of the CMA 270 rather than a single instantaneous reading indicative of the end of life (e.g., 70% charging capacity) provides additional information to classify a CMA 270 for reconditioning to an appropriate use. In some embodiments, not every data point associated with a useful life indicator is stored, for example temperature may be sampled and stored on a weekly basis rather than daily basis. CMAs 270 may be classified where different classifications are suitable for use in different second lives or based on different expected future performance in the second life as determined by the evaluation of the useful life indicators from the first life. Tracking useful life indicators also provides the CMA 270 manufacturer with data that can be used for diagnostics to determine why a particular CMA 270 performs better or worse than a similar CMA 270 and then use that diagnostic information to improve manufacturing or other processes for new CMAs.
For example, a CMA 270 with 70% charging capacity, but a relatively high number of days operated in extreme temperature conditions may have its charging capacity degrade at a faster rate than a CMA 270 with a 70% charging capacity and no days operated in extreme temperature conditions. Both CMAs 270 may be suitable for reconditioning and use in their second lives, but the appropriate uses for the two CMAs 270 in their second lives may be different based on their classification resulting from evaluation of their respective useful indicators. Tracking and storage of useful life indicators can also be used to evaluate returned or warrantied battery packs, fix or refurbish battery packs returned within their first life, and improve manufacturing processes by comparing various CMAs 270 to one another.
The useful life indicators are used to identify when a CMA 270 has reached an end of life threshold. The CMA 270 may have multiple end of life thresholds. For example, the CMA 270 may be suitable for use in a first application during the span of its first life (e.g., a commercial lawn mower). When the CMA 270 reaches its first end of life threshold (e.g., 80%, 75%, 70%, etc. of its useful life), the CMA 270 is taken out of service for the first application and returned to the CMA 270 manufacturer. The CMA 270 manufacture then categorizes or classifies the CMA 270 based on its useful life data to identify a suitable second life application for that particular CMA. If necessary, that CMA 270 is reconditioned or refurbished and then combined with other similarly classified CMAs 270 to form a battery pack 100 for use in a second life application. This new battery pack 100 can be used in the second life application until the CMA 270 reaches a second end of life threshold (e.g., 50%, 45%, 40%, etc. of its useful life). This method of using the same CMA 270 for different applications based on the CMA's life cycle allows the CMA 270 manufacturer to take greater advantage of the CMA's available capacity by using the CMA 270 in multiple applications. Instead of having a CMA 270 at the end of its first life discarded and not using the remaining battery capacity of the CMA 270, the CMA 270 may be used in multiple applications. The serviceability of the battery pack 100 with conventional service tools beneficially allows the CMAs 270 to be removed and replaced for second life applications.
The CMA 270 manufacturer may lease battery packs consisting of multiple CMAs 270 to the user of the equipment powered by the battery pack 100. This approach would enable the user of the CMA 270 during its first life to return the battery pack 100 at the end of its first life to the CMA 270 manufacturer, allowing the CMA 270 manufacturer to classify the CMAs 270 and reuse them for second life applications, where the resulting battery packs could again be leased or sold to the user of the equipment powered by the battery pack 100 consisting of CMAs 270 in their second life. Alternatively, the CMA 270 manufacture can sell the battery pack 100 consisting of CMAs 270 and buy back the battery pack 100 at the end of the first life of the CMAs 270 for classification and reuse in a second life application.
The BMS 222 can be configured to identify which CMA 270 in the battery pack 100 is in need of servicing. For example, the BMS 222 may determine which CMA 270 experienced a failure in the battery pack 100. In some embodiments, to determine the faulty CMA, the BMS 222 measures readings of each voltage tap on each CMA 270. For example, the BMS 222 monitors each of the voltage taps 214 on each of the CMAs 270 and determines if the reading on each voltage tap 214 deviates from an expected measurement. The BMS 222 can be configured to trigger a service alarm for a faulty CMA. For example, when monitoring current draw patterns, if a CMA 270 is the first to hit a top voltage level or the first to hit a bottom voltage level (e.g., zero voltage), the BMS 222 identifies the “bad” CMA and triggers a service alarm. The BMS 222 may also monitor which CMA 270 in the battery pack 100 is first to charge or discharge in order to identify a malfunctioning CMA. Advantageously, the battery pack 100 is configured to be serviceable. As such, when a CMA is identified as faulty by the BMS 222, the individual CMA can be swapped out for a functional CMA 270. In some embodiments, the BMS 222 also monitors and stores the temperature of each CMA 270 within the battery pack 100 using data received from a temperature sensor coupled to each CMA 270 (e.g., thermistors 217).
The BMS 222 includes several connectors on one side of the BMS 222. The input and output components of the BMS 222 may be fused to the BMS 222 with resettable fuses. In some embodiments, a BMS cover 224 is positioned surrounding the BMS 222. The BMS cover 224 can provide protection for the BMS 222 and the connectors and connections to various harnesses coupled to the BMS 222. In some embodiments, the BMS cover 224 is a structural potting box that is crush and impact resistant, as well as metal, thermal, and electronic magnetic interference (EMI) resistant. The BMS 222 includes thermistor connectors 226 for monitoring temperature of each of the CMAs 270 of the battery pack 100. The BMS 222 includes CMA voltage connectors 220 to receive data on the operation of the battery cells 202 and CMAs 270 throughout the battery pack 100. In some embodiments, a measurement read at positive voltage tap 232 is communicated to the BMS 222 via the CMA voltage connectors 220. Each connector of the BMS 222 may couple to a connection harness, similar to contactor harness 228 or shunt harness 230.
In some embodiments, the BMS 222 includes a pre-charge circuit and a bleed circuit integrated into the same board of the BMS 222. In some embodiments, the BMS 222 conducts a current profile of the battery pack 100 to detect what components are plugged into the battery pack 100. When an abnormal profile of the battery pack 100 is detected, the BMS 222 may signal an alarm as a notification of the abnormality. In some embodiments, when the battery pack 100 is connected in parallel or series with another battery pack, the BMS 222 writes to the neighboring BMS of the connected battery pack to update the old firmware with the newest firmware. The BMS 222 can also be configured to update a charger, or other energy source, for the battery pack 100 with newer firmware and can receive updates from the charger with newer firmware. In some embodiments, the BMS 222 can operate in three different states, recharge, charge, and hybrid. During the hybrid state, the BMS 222 may effectively charge the battery pack 100 when meant to be discharging, with or without communication. While charging, the BMS 222 may use adaptive charge limits. For example, if receiving regenerative charging, where the charge of battery pack 100 is being topped off, the BMS 222 may lower the top end charge limit to avoid a top end fault due to regenerative charging. The decision of the BMS 222 to lower the top end charge limit may be based on a frequency of fault occurrence. In another example, the BMS 222 may change the top end charge to 4.2 volts to prevent reaching a top end fault, when originally the top end charge was 4.1 volts per CMA 270.
The battery pack 100 is also shown to include CMA-to-CMA interlock 204. The CMA-to-CMA interlock 204 may allow the several CMAs 270 to be mounted in a parallel configuration. An end-of-string mount assembly 212 is also shown in battery pack 100. The end-of-string mount assembly 212 may be used at both ends of a tier of the battery pack 100 to terminate connection when a CMA 270 does not connect to another CMA 270. In some embodiments, the end-of-string mount assembly 212 is coupled to a negative collector plate 254. The negative collector plate 254 can extend outward from one side of the bottom CMA cell holder frame of a CMA 270. In some embodiments, the negative collector plate 254 extends away from an outermost set of pockets of the bottom CMA cell holder frame of the CMA 270 to form a generally planar bottom surface that is coupled to the end-of-string mount assembly 212.
The battery pack 100 is also shown to include a communication harness 236, a negative cable assembly 238, a contactor-to-contactor busbar 240, a positive cable assembly 242, a positive terminal-to-contactor busbar 244, a positive terminal 106, a pass-through data connector 104, a negative terminal 102, battery pack dual contactors 250, contactor coil terminals 252, negative CMA-to-ground cable assembly 256, series tier flexible busbars 258, shunt isolators 262, and CMA cell holder 264. In some embodiments, the communication harness 236 connects the pass-through data connector 104 to the BMS 222. In some embodiments, the pass-through data connector 104 couples to the pass-through data connector 104 on the front panel of the housing 108 for the battery pack 100. The negative CMA-to-ground cable assembly 256 may run underneath the battery pack 100 and up to an end-of-string mount assembly 212, using negative cable routing, from the first CMA 270 block to the ground 272 of the last CMA 270 block. In some embodiments, the negative CMA-to-ground assembly is routed from a first CMA 270 on the top tier of the battery pack 100, down the front side (e.g., as shown in
A top view 300 of the battery pack 100 is shown in
Referring now specifically to
The battery cells 202 in each CMA 270 of the battery pack 100 can be placed in electrical communication with one another using a bottom collector plate (e.g., bottom collector plate 404) and a top collector plate. The collector plates can be formed of an electrically conducting metallic material (e.g., copper, aluminum) that can receive and conduct current through terminals extending away from each battery cell 202. The thickness of the top and bottom collector plates can be selected to carry an amount of current without significant raise in the temperature of the collector plates. The thickness of the collector plates may also give current pass-through point sufficient area at lap joints between plates and torque requirements for clamping plates and spreading out clamp forces. The bolting patterns of the collector plates can allow symmetrical, even flow of current across each CMA. In some embodiments, each of the battery cells 202 includes a positive terminal connected to the top collector plate and a negative terminal connected to the bottom collector plate. Conversely, each of the positive terminals could be connected to the bottom collector plate, while each of the negative terminals could be connected to the top collector plate.
Each of the collector plates can include a series of apertures formed through a generally rectangular base. The number of apertures formed through each collector plate can correspond to the number of battery cells 202 that are present in or that could be present in the CMA 270. The bottom collector plate can be coupled to a bottom CMA cell holder frame 704 (
The top and bottom collector plates (e.g., the bottom collector plates 404) each have generally complimentary geometry to seat upon the bottom CMA cell holder frame 704 and the top CMA cell holder frame 702. For example, the apertures of top collector plates and bottom collector plates 404 can be defined by a generally elongate oval shape that can be received around locating features of the top CMA cell holder frame 702 and the bottom CMA cell holder frame 704. The shape of the apertures can form a clearance fit around the locating features to help position the top collector plates and bottom collector plates 404 during assembly of the CMA.
Referring now to
Each CMA 270 in the battery pack 100 is the same as the others in the battery pack 100 and includes an end connection with an interface to provide up or down routing or terminate, since the “end” CMA 270 does not connect to another CMA 270. The end connection component of each CMA 270 is common to connect to other CMAs 270 of the battery pack 100. In some embodiments, one or more of the CMAs 270 in the battery pack 100 may have the same form factor as a CMA 270 without “power control,” but may also include a contactor, a current sensor (e.g., a shunt resistor), and a BMS controller to manage the power of the CMA 270 “power control” block.
The battery cells 202 of the CMA 270 are depicted. In some embodiments, all thirty-two battery cells 202 are connected in parallel in a 1S32P (one series, thirty-two parallel) arrangement by a single top collector plate (e.g., positive collector plate 266) and a single bottom collector plate (e.g., negative collector plate 254), with all the battery cells 202 pointed in a single direction. In other embodiments, two groups of sixteen battery cells 202 are connected in parallel with the two groups connected in series in a 2S16P (two series, sixteen parallel) arrangement. In some embodiments, the battery cells 202 may be connected in parallel from a 1S16P (one series, sixteen parallel) arrangement, while in other embodiments the battery cells 202 may be connected in a 2S32P (two series, thirty-two parallel) arrangement with a contactor plate change. Top collector plates and bottom collector plates can be used to connect the thirty-two battery cells 202. In some embodiments, each top collector plate and each bottom collector plate can support and connect sixteen battery cells 202 in parallel. The two sets of sixteen battery cells 202 can then be electrically coupled together to place the sets of sixteen battery cells 202 in series with one another. Arranging a relatively large number of battery cells 202 in parallel in this manner helps to slow the degradation of the charge capacity of the CMA 270. In other embodiments, the number of battery cells 202 in the CMA 270 may be greater or fewer and the connection arrangements between the battery cells 202 may vary depending on the ratings needed from a particular CMA 270 (e.g., voltage, capacity, power, etc.). Each battery cell 202 has a positive terminal and a negative terminal.
Referring now to
Referring now to
The top CMA cell holder frame 702 can include many of the same features present in the bottom CMA cell holder frame 704. Because the top CMA cell holder frame 702 may be a substantial mirror image of the bottom CMA cell holder frame 704 in some embodiments, components present in the top CMA cell holder frame 702 having common names in both the bottom CMA cell holder frame 704 and the top CMA cell holder frame 702 should be considered to have the same or substantially similar geometries, orientations, structures, or relationships to other components as described with reference to the bottom CMA cell holder frame 704. The top CMA cell holder frame 702 also includes a generally rectangular base. A series of cylindrical protrusions may extend upwardly away from the base to define another series of pockets that can each receive a battery cell 202. Each pocket can include a generally circular base circumscribed by the cylindrical protrusion associated with the pocket. A terminal hole can be formed through the base. Windows can be formed in the base and/or the cylindrical protrusions to define adhesive flow paths through the top CMA cell holder frame 704 onto the battery cells 202 positioned within the pockets. The top surface of the top CMA cell holder frame 702 may include recesses formed into the top CMA cell holder frame 702 to define adhesive flow paths. The recesses can direct curable adhesive around battery cells 202 during the CMA 270 assembly process, which can help create a robust coupling between battery cells 202 and the top CMA cell holder frame 702. Furthermore, the curable adhesive may be used to couple the top collector plates (e.g., positive collector plate 266) to the top CMA cell holder frames 702.
In some embodiments, the CMAs 270 may be scaled to adjust to change in lengths and diameters of the battery cells 202 used for the CMAs 270. The top CMA cell holder frame 702 and the bottom CMA cell holder frame 704 may be varying lengths depending on the number of cells used in the CMAs 270 and the type of battery cells 202 used for each CMA 270. For example, the pockets of the top CMA cell holder frame 702 and the bottom CMA cell holder frame 704 may vary in cylindrical cell form factors depending on the diameters of the battery cells 202 utilized in the battery pack 100. The battery pack 100 may also be assembled to use longer or shorter battery cells 202, in which case the top CMA cell holder frame 702 and the bottom CMA cell holder frame 704 may be closer together in height or father apart in height. In some embodiments, when battery cells 202 have a different diameter, the same mounting points (e.g., bolt patterns) for each CMA 270 is used for the construction of the CMAs 270, but the top CMA cell holder frame 702 and the bottom CMA cell holder frame 704 have altered pocket sizes to accept the different battery cells 202.
The spacers 209 can be defined by a height (i.e., a longitudinal length) that is larger than a height of each battery cell 202. By being taller than the battery cells 202, compressive loading experienced by either of the top CMA cell holder frame 702 or the bottom CMA cell holder frame 704 is initially diverted to the spacers 209, which engage the collars of the frames. The spacers 209 keep the bottom CMA cell holder frame 704 and the top CMA cell holder frame 702 at a fixed distance apart from one another, which prevents the top CMA cell holder frame 702 and the bottom CMA cell holder frame 704 from applying extreme or otherwise unwanted compressive stress to each battery cell 202 that could be caused by loading from another CMA 270 positioned in a tier of the battery pack 100 above the CMA 270, for example.
Referring now to
In some embodiments, the first compartment 802 may include one or more panels and/or ports that physically and electrically couple to one or more other compartments in the battery pack 100. The pass-through data connector 104 and pass-through terminals 105, including negative terminal 102 and positive terminal 106, are accessible from the exterior of the housing 108. As such, the pass-through data connector 104 and pass-through terminals 105 “pass-through” a front panel 803 (e.g., a panel covering the front view 600 of
The second compartment 804 includes the BMS 222, a first tier of CMAs 275, a second tier of CMAs 277, and a third tier of CMAs 279, positioned as shown in
The second compartment 804 can include an external access point into the second compartment 804 that is separate and independent from the first compartment 802. For example, and as depicted in
The battery pack 100 may require service during its lifetime. Varying levels of serviceability are provided for an operator to access different components of the battery pack 100. Accordingly, each compartment of the battery pack 100 has a different serviceability level. The different serviceability levels can be based upon the necessary authorization needed to access the battery pack 100. As such, components located within separate compartments may have different serviceability levels. As described herein, components having the same level of serviceability refers to components being accessible for servicing without the operator needing to bypass additional securing mechanisms or other security to access the components. For example, components accessible from the outside of the battery pack 100 have a higher level of serviceability than components in the first compartment 802, nested within the housing of the battery pack 100. In some embodiments, a lower level of serviceability is associated with a compartment nested within another compartment with a higher level of serviceability. For example, components in the first compartment 802 of the battery pack 100 have a higher level of serviceability than components in the second compartment 804 of the battery pack 100. An operator may access and service the components in the first compartment 802 before gaining access to components in the second compartment 804 by bypassing a securing mechanism. As such, the operator may then service the components in the second compartment 804 with the lower level of serviceability.
The battery pack 100 has a first level of serviceability. This first level of serviceability may include cosmetics and diagnostics of the battery pack 100. Cosmetic components of the battery pack 100 can include the exterior components of the battery pack 100. For example, a first level of serviceability includes repairing any cracks or breaks in the external housing 108, such as a side plate of the housing 108 shown in
Each compartment located within the housing 108 of the battery pack 100 may have a different access point and a different level of access. For example, the first compartment 802 has a first access point (e.g., the panel 803) with a securing mechanism (e.g., the fasteners 805) and the second compartment 804 has a second access point (e.g., the top panel 807) with a second securing mechanism (e.g., the locking mechanism 809). In some embodiments, the access point of the second compartment 804 is more internal (e.g., further from the housing 108, nearer the center of the battery pack 100, formed through a wall of the first compartment 802, etc.) than the first access point of the first compartment 802, which can be the front panel 803. In some embodiments, the first compartment 802 is accessible by a first securing mechanism having a first level of security. As depicted in
Turning now to
In some embodiments, the components within the first compartment 802 may be integrated into a block that is the same or similar as each of the blocks of CMAs 270. For example, all of the components of the first compartment 802 may be built-into a “controls” block with the same form factor as the form factor of the blocks of CMAs 270 within the second compartment 804. In some embodiments, this “controls” block module component, structured similar to the module blocks of CMAs 270, includes the BMS 222, disconnect device 253 (e.g., dual contactors 250), and the shunt 251. This “controls” block module component may have the same form factor as the blocks of CMAs 270 in order to bolt the “controls” block, module component easily into place during construction of the battery pack 100. By including these components of the battery pack 100 in a single module similar to the blocks of CMAs 270, it may be much simpler to replace the logic components if one of them fails. In another embodiment, the disconnect device 253 may be integrated into a single module with power buds, such that there are no live connections that are unprotected in the module with the disconnect device 253. In some embodiments, a module component with the disconnect device 253 may include an outlet to couple to the first compartment 802 for simplified access to service the disconnect device 253. In some embodiments, the disconnect device 253 may have other receptacles to allow easy removal of the connection in order to service the power connections (e.g., 12V, GNDA, GNDB) of the battery pack 100.
The block diagram of
In some embodiments, the shunt 251 is positioned in a third compartment 902. In some embodiments, the third compartment 902 is positioned in a separate compartment from both the first compartment 802 and the second compartment 804. By positioning the shunt 251 in a separate compartment from the first compartment 802, the disconnect device 253 and the shunt 251 are separated. Therefore, positive and negative components of the battery pack 100 are separated and the risk of a short circuit while servicing the battery pack 100 can be further reduced. For example, a wrench could short circuit the battery pack 100 if the wrench were to connect the shunt 251 to the positive busbar (e.g., positive terminal-to-contactor busbar 244), bypassing the disconnect device 253. By placing the shunt 251 outside of the first compartment 802, this possibility is eliminated while servicing the components within the first compartment 802. Furthermore, the shunt 251 may be a component that does not require servicing as often as other components of the battery pack 100 (e.g., disconnect device 253, BMS 222, wiring harness 235, etc.). As such, it may be uncommon for the need to access the more insulated, third compartment 902 in order to service the shunt 251. In some embodiments, the shunt 251 is positioned in a third compartment 902 proximate a bottom side of the battery pack 100. In some embodiments, the shunt 251 is used as a fuse for the battery pack 100 in a fuse panel proximate the bottom side of the third tier of CMAs 279. In other embodiments, the shunt 251 may be positioned proximate a back side (e.g., within the rear view 500 of
In other embodiments, the first compartment 802 may include fewer components than is shown in the block diagram of
As used herein, the term “circuit” may include hardware structured to execute the functions described herein. In some embodiments, each respective “circuit” may include machine-readable media for configuring the hardware to execute the functions described herein. The circuit may be embodied as one or more circuitry components including, but not limited to, processing circuitry, network interfaces, peripheral devices, input devices, output devices, sensors, etc. In some embodiments, a circuit may take the form of one or more analog circuits, electronic circuits (e.g., integrated circuits (IC), discrete circuits, system on a chip (SOCs) circuits, etc.), telecommunication circuits, hybrid circuits, and any other type of “circuit.” In this regard, the “circuit” may include any type of component for accomplishing or facilitating achievement of the operations described herein. For example, a circuit as described herein may include one or more transistors, logic gates (e.g., NAND, AND, NOR, OR, XOR, NOT, XNOR, etc.), resistors, multiplexers, registers, capacitors, inductors, diodes, wiring, and so on).
The “circuit” may also include one or more processors communicably coupled to one or more memory or memory devices. In this regard, the one or more processors may execute instructions stored in the memory or may execute instructions otherwise accessible to the one or more processors. In some embodiments, the one or more processors may be embodied in various ways. The one or more processors may be constructed in a manner sufficient to perform at least the operations described herein. In some embodiments, the one or more processors may be shared by multiple circuits (e.g., circuit A and circuit B may comprise or otherwise share the same processor which, in some example embodiments, may execute instructions stored, or otherwise accessed, via different areas of memory). Alternatively or additionally, the one or more processors may be structured to perform or otherwise execute certain operations independent of one or more co-processors. In other example embodiments, two or more processors may be coupled via a bus to enable independent, parallel, pipelined, or multi-threaded instruction execution. Each processor may be implemented as one or more general-purpose processors, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), or other suitable electronic data processing components structured to execute instructions provided by memory. The one or more processors may take the form of a single core processor, multi-core processor (e.g., a dual core processor, triple core processor, quad core processor, etc.), microprocessor, etc. In some embodiments, the one or more processors may be external to the apparatus, for example the one or more processors may be a remote processor (e.g., a cloud based processor). Alternatively or additionally, the one or more processors may be internal and/or local to the apparatus. In this regard, a given circuit or components thereof may be disposed locally (e.g., as part of a local server, a local computing system, etc.) or remotely (e.g., as part of a remote server such as a cloud based server). To that end, a “circuit” as described herein may include components that are distributed across one or more locations.
An exemplary system for implementing the overall system or portions of the embodiments might include a general purpose computing computers in the form of computers, including a processing unit, a system memory, and a system bus that couples various system components including the system memory to the processing unit. Each memory device may include non-transient volatile storage media, non-volatile storage media, non-transitory storage media (e.g., one or more volatile and/or non-volatile memories), etc. In some embodiments, the non-volatile media may take the form of ROM, flash memory (e.g., flash memory such as NAND, 3D NAND, NOR, 3D NOR, etc.), EEPROM, MRAM, magnetic storage, hard discs, optical discs, etc. In other embodiments, the volatile storage media may take the form of RAM, TRAM, ZRAM, etc. Combinations of the above are also included within the scope of machine-readable media. In this regard, machine-executable instructions comprise, for example, instructions and data which cause a general purpose computer, special purpose computer, or special purpose processing machines to perform a certain function or group of functions. Each respective memory device may be operable to maintain or otherwise store information relating to the operations performed by one or more associated circuits, including processor instructions and related data (e.g., database components, object code components, script components, etc.), in accordance with the example embodiments described herein.
The construction and arrangements of the present disclosure, as shown in the various exemplary embodiments, are illustrative only. Although only a few embodiments have been described in detail in this disclosure, many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter described herein. Some elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. The order or sequence of any process, logical algorithm, or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may also be made in the design, operating conditions and arrangement of the various exemplary embodiments without departing from the scope of the present invention.
This application claims priority to U.S. Provisional Patent Application No. 62/968,729, filed Jan. 31, 2020, the content of which is hereby incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2021/050686 | 1/28/2021 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 62968729 | Jan 2020 | US |
