Patent Application
20240079749
The present invention relates to a power supply device and a method of manufacturing the device.
A power supply device that includes a lot of secondary battery cells connected in series and parallel to one another is used as a backup power supply for a server or as a power supply device in applications to stationary batteries for home appliances, business facilities, and plants. The applications further include power sources for driving vehicles such as a hybrid vehicle, an electric vehicle, an electric cart, and an electric scooter, and also include electric power sources for driving a power-assisted bicycle and an electric power tool. Such a power supply device is provided with a lot of secondary battery cells connected in series, thereby being intended to supply a higher power output.
For example, power supply device 600 illustrated in the exploded perspective view of
The power supply device includes overvoltage-detecting fuses configured to blow upon detecting an overvoltage in order to protect the secondary battery cells from the overvoltage. A circuit diagram of the power supply device including such overvoltage-detecting fuses is shown in
In circuit unit 603, connection terminals 641 are connected to controller 646, thereby allowing controller 646 to monitor the voltages of secondary battery cells 601. Controller 646 is also connected to the gate of resistance-heating switching element 650. When determining that the voltage of secondary battery cell 601 is in an abnormal state such as an overvoltage, the controller turns on resistance-heating switching element 650 to cause heating resistor 634b to heat, thereby blowing thermal fuses 634a.
In assembling such a power supply device, from the viewpoint of workability, random connection has been demanded which allows an unspecified order of connections between the power supply device and the series-connection parts of a cell block. Unfortunately, in connecting the circuit board having the overvoltage-detecting fuses to the series-connection parts in which a lot of secondary battery cells are connected in series, it has posed a problem as follows: When the random connection is carried out for the board including a circuit section that contains the overvoltage-detecting fuses capable of turning into a blown path, the overvoltage-detecting fuses are sometimes erroneously caused to blow due to, such as, the instantaneously detecting operation carried out by an overvoltage protection IC during the random connection. As illustrated in
An object of the present invention is to provide a power supply device that avoids an erroneous blowout of a fuse during assembling the device and improves workability in the assembling, and a method of manufacturing the power supply device.
To achieve the above object, a method of manufacturing a power supply device according to a first aspect of the present invention that includes a battery unit and a circuit unit electrically connected to the battery unit and configured to control charging and discharging of the battery unit. The battery unit includes a series connection including secondary battery cells connected at least in series to one another, a battery-side ground on a low-voltage side of the series connection, and a battery-side output on a high-voltage side of the series connection. The circuit unit includes an overvoltage-detecting fuse configured to detect an overvoltage and to blow upon detecting the overvoltage. In the method, one or more battery-side intermediate terminals disposed in the battery unit are connected to respective one or more circuit-side intermediate terminals disposed in the circuit unit while a detachable lead member configured to connect the overvoltage-detecting fuse to the battery-side output is detached. The one or more battery-side intermediate terminals are electrically connected to intermediate potentials of at least a part of the secondary battery cells connected in series to one another. The overvoltage-detecting fuse is connected to the battery-side output by fixing the lead member to the circuit unit. In this configuration, the detachment of the detachable lead member during assembling the power supply device allows the overvoltage-detecting fuse of the circuit unit to be electrically separated, thereby avoiding a possible situation where the overvoltage-detecting fuse erroneously blows in connecting the battery-side intermediate terminals of the battery unit to the circuit-side intermediate terminals of the circuit unit. Further, the detachment enables random connection between the battery-side intermediate terminals and the circuit-side intermediate terminals, which resultantly enhancing workability of connecting between the circuit unit and the battery unit, leading to an increase of manufacturing efficiency.
In a method of manufacturing a power supply device according to a second aspect of the present invention is, in the method described above, the circuit unit includes an overvoltage protection circuit configured to monitor an overvoltage of at least one of the plurality of secondary battery cells. The overvoltage protection circuit is configured to blow the overvoltage-detecting fuse upon detecting the overvoltage of the secondary battery cells. In this configuration, the electrical separation of the overvoltage-detecting fuse provides the following advantage. That is, in assembling the power supply device, even if a signal of erroneously detecting an overvoltage is sent when electrically connecting the overvoltage protection circuit, the electrical separation prevents the overvoltage-detecting fuse from blowing, thereby protecting the power supply device from an unintended failure during the assembling.
A power supply device according to a third aspect of the present invention includes a battery unit and a circuit unit connected to the battery unit. The battery unit includes a series connection including a plurality of secondary battery cells connected at least in series to one another, a battery-side ground on a low-voltage side of the series connection, and a battery-side output on a high-voltage side of the series connection. The battery unit includes one or more battery-side intermediate terminals electrically connected to intermediate potentials of at least a part of the plurality of secondary battery cells connected in series. The circuit unit includes: one or more circuit-side intermediate terminals connected to at least one of the plurality of secondary battery cells via the one or more battery-side intermediate terminals; an overvoltage-detecting fuse connected to the battery-side output, the overvoltage-detecting fuse being configured to detect an overvoltage of the plurality of secondary battery cells and to blow upon detecting the overvoltage; and a detachable lead member interposed between the overvoltage-detecting fuse and the battery-side output. In this configuration described above, the detachment of the detachable lead member during assembling the power supply device allows the overvoltage-detecting fuse of the circuit unit to be electrically separated, which avoids a possible situation where the overvoltage-detecting fuse erroneously blows in connecting the battery-side intermediate terminals of the battery unit to the circuit-side intermediate terminals of the circuit unit. The detachment of the lead member enables random connection between the battery-side intermediate terminals and the circuit-side intermediate terminals, which results in an increase in workability of connecting between the circuit unit and the battery unit, leading to an increased manufacturing efficiency.
In a power supply device according to a fourth aspect of the present invention, in any one of the aspects described above, the circuit unit further includes an overvoltage protection circuit configured to monitor the overvoltage of the plurality of secondary battery cells. The overvoltage protection circuit is configured to blow the overvoltage-detecting fuse upon detecting the overvoltage of the secondary battery cells. This configuration described above provides the following advantage. That is, in assembling the power supply device, even if an overvoltage is erroneously detected when electrically connecting the overvoltage protection circuit, it is possible to avoid a situation where the overvoltage-detecting fuse blows, thereby protecting the power supply device from an unintended failure during the assembling.
In a power supply device according to a fifth aspect of the present invention, in any one of the aspects described above, the lead member is a metal bus bar. This configuration facilitates attaching and detaching the lead member, capable of passing a large current through it, to and from the circuit unit.
In a power supply device according to a sixth aspect of the present invention, in any one of the aspects described above, the lead member includes either a wire clip or a lead wire with a connector.
A power supply device according to a seventh aspect of the present invention includes a battery unit and a circuit unit connected to the battery unit. The battery unit includes a series connection including a plurality of secondary battery cells connected at least in series to one another, a battery-side ground on a low-voltage side of the series connection, and a battery-side output on a high-voltage side of the series connection. The battery unit includes one or more battery-side intermediate terminals electrically connected to intermediate potentials of at least a part of the plurality of secondary battery cells connected in series to one another. The circuit unit includes: one or more circuit-side intermediate terminals connected to at least one of the plurality of secondary battery cells via the one or more battery-side intermediate terminals; and an overvoltage-detecting fuse connected to the battery-side output, the overvoltage-detecting fuse being configured to detect an overvoltage of the plurality of secondary battery cells and to blow upon detecting the overvoltage. The overvoltage-detecting fuse includes: two thermal fuses connected in series to each other at a connection point; and a heating resistor having one end connected to the connection point of the thermal fuses, the heating resistor being configured to generate heat upon being energized so as to blow the thermal fuses. The overvoltage-detecting fuse constitutes a unit detachable from the circuit unit. In this configuration described above, the detachment of the detachable lead member during assembling the power supply device allows the overvoltage-detecting fuse of the circuit unit to be electrically separated, which avoids a possible situation where the overvoltage-detecting fuse is erroneously caused to blow in connecting the battery-side intermediate terminals of the battery unit to the circuit-side intermediate terminals of the circuit unit. The detachment of the lead member enables random connection between the battery-side intermediate terminals and the circuit-side intermediate terminals, which results in an increase in workability of connecting between the circuit unit and the battery unit, leading to an increased manufacturing efficiency.
Hereinafter exemplarily embodiments of the present invention will be described with reference to the accompanying drawings. However, the exemplary embodiments described below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following description. Moreover, this specification never limits the members described in the claims to the members of the exemplary embodiments. Unless otherwise specified, the dimensions, materials, shapes, relative positions, and the like of the configuration components described in the exemplary embodiments are not intended to limit the scope of the present invention but are merely illustrative examples. It should be noted that the sizes, positional relationship, and the like of members illustrated in the drawings may be exaggerated for clarity of explanation. Furthermore, in the following description, the same names and reference numerals indicate the same or similar members, and detailed description will be appropriately omitted. Furthermore, regarding elements that configure the present invention, a plurality of elements may be composed of the same member so that one member serves as a plurality of elements, or conversely, the function of one member can be shared and achieved by a plurality of members.
A power supply device according to the present invention is used in various applications that include backup power supplies for servers, power supplies mounted on electric-powered vehicles such as a hybrid vehicle and an electric vehicle for supplying electric power to vehicle's running motors, power supplies for storing electric power generated by such as photovoltaic power generation and wind power generation from natural energies, and power supplies for storing late-night electric power. Such a power supply device is used, in particular, as a power supply preferably used in high-power, large-current applications. Hereinafter, a power supply device to be used as a backup power supply for a server will be described as one exemplary embodiment of the present invention.
Power supply device 100 according to Exemplarily Embodiment 1 of the present invention is illustrated in an exploded perspective view of
Each secondary battery cell 1 is a cylindrical secondary battery cell with an outer case having a cylindrical shape. Cylindrical secondary battery cell 1 has electrode surfaces on both end surfaces thereof. Secondary battery cells 1 are connected at least in series to one another. Secondary battery cells 1 connected in series to one another are preferably connected in parallel to other secondary battery cells 1 connected in series to one another. The output of a battery assembly group composed of secondary battery cells 1 that involve such series connections is supplied from power supply device 100. Secondary battery cells 1 are cylindrical lithium-ion secondary batteries. However, that the secondary battery cells of the power supply device according to the present invention are not limited to the cylindrical batteries and also to the lithium-ion secondary batteries. All types of rechargeable batteries such as a nickel-hydrogen battery cell are also applicable to the battery cells.
Battery unit 2 is for holding secondary battery cells 1. Battery unit 2 includes battery holder 10 including battery-holding parts each having a cylindrical shape into which cylindrical secondary battery cell 1 can be inserted. In battery holder 10 of
Battery holder 10 is divided into sub-holders sandwiching secondary battery cells 1 from both sides. The middle portions of secondary battery cells 1 are exposed from the sub-holders. While secondary battery cells 1 are sandwiched by respective pairs of the sub-holders, lead plates 20 are fixed on the side surfaces of battery holder 10 and lead plates 20 are welded to secondary battery cells 1. To position lead plates 20 at predetermined locations, each side surface of battery holder 10 has guides for positioning the leads. The guides are fit to the respective contours of lead plates 20.
In addition, battery holder 10 includes lead plates 20 and battery-side ground terminal 30. The lead plates 20 each includes battery-side intermediate terminal 21. Battery-side intermediate terminal 21 is electrically connected to at least one of secondary battery cells 1.
All lead plates 20 are disposed on the side surfaces of battery holder 10 and connected to the electrode surfaces of secondary battery cells 1. Lead plates 20 are for connecting secondary battery cells 1 in series and parallel to one another. In the case of high-capacity secondary battery cells 1 such as lithium-ion secondary batteries, for the purpose of detecting the state of each secondary battery cell 1, the potential of each of lead plates 20 is detected, which allows the voltage of an assembly group of secondary battery cells 1 connected in parallel to lead plate 20 in question to be detected. In this example, the battery assembly group is composed of a total of 42 secondary battery cells 1 in which the 42 cells of secondary battery cells 1 are connected in parallel every 6 secondary battery, cells 1, which makes a set, into 7 sets, and the 7 sets are connected in series.
Lead plates 20 each electrically and mutually connects electrode terminals of adjacent secondary battery cells 1. Further, a lead plate out of lead plates 20 which serves as the ground side of the total output of a battery-connected body including secondary battery cells 1 electrically connected in series to one another is referred to as ground lead plate 20G. Battery-side ground terminal 30 is connected to ground lead plate 20G. In contrast, a lead plate serving as the HIGH side of the total output of the battery-connected body is referred to as output lead plate 20H.
Battery-side ground terminal 30 is connected to the ground side of the total output of secondary battery cells 1 electrically connected in series and/or parallel to one another. Battery-side ground terminal 30 is drawn outside from battery holder 10.
The upper surface of battery holder 10 is used as mounting surface 11 on which circuit board 40 is mounted. A frame body for holding the circuit board may be formed on the board-mounting surface. Alternatively, a board holder for holding the circuit board may be disposed separately.
Circuit board 40 is mounted on mounting surface 11. Electronic circuits are mounted on circuit board 40. Such circuit include a voltage-detecting circuit to detect potentials of intermediate portions of the battery assembly group in which secondary battery cells 1 are connected in series and parallel, a control circuit to control charging and discharging, and a safety circuit. The intermediate potentials of secondary battery cells 1 connected in series to constitute the battery assembly group are detected based on the voltages of the potential lead plates 20 and are supplied to the voltage-detecting circuit.
A circuit diagram of power supply device 100 is shown in
Battery unit 2 includes secondary battery cells 1. The secondary battery cells 1 are connected in series to one another. Although not shown in
As shown in
In charging-discharging path CP connecting between the connection terminal and external charging terminal 48, fuse module 34, charging switching element 44, and discharging switching element 45 are connected in series. The gate of charging switching element 44 and the gate of discharging switching element 45 are connected to controller 43.
In the example of
Fuse module 34 includes thermal fuses 34a and 34a connected in series to each other at a connection point, and heating resistor 34b with one end connected to the connection point. The other end of heating resistor 34b of fuse module 34 is connected to controller 43. The other end may be connected via a resistance-heating switching element to a conductive path that connects between battery-side intermediate terminal 21 and external terminal 49. In this case, the gate of the resistance-heating switching element is connected to controller 43 and the resistance-heating switching element is controlled by controller 43, thereby controlling the operation of heating resistor 34b.
Circuit unit 3 includes a circuit board on which electronic components that constitutes such as a charging-discharging circuit and an overvoltage protection circuit are mounted. Circuit unit 3 includes circuit-side intermediate terminals 41, external discharging-terminal 47, external charging-terminal 48, controller 43, fuse module 34, lead member 50, charging switching element 44, discharging switching element 45, and second overvoltage protection circuit 43B. Circuit-side intermediate terminals 41 are connected to at least one of secondary battery cells 1 via one or more battery-side intermediate terminals 21.
Controller 43 charges and discharges battery unit 2 by controlling charging switching element 44 and discharging switching element 45. Charging switching element 44 and discharging switching element 45 are preferably FETs. Further, the FETs may be of a p-channel type other than the n-channel type illustrated in
Controller 43 constitutes an overvoltage protection circuit. That is, the controller monitors intermediate potentials in the series connection of secondary battery cells 1 via battery-side intermediate terminals 21 and circuit-side intermediate terminals 41. When the intermediate potentials reach a predetermined voltage, the controller regards them as being at an overvoltage, and thus causes fuse module 34 to operate to interrupt the current.
In addition, circuit unit 3 includes second overvoltage protection circuit 43B. Second overvoltage protection circuit 43B monitors the charging current during charging of battery unit 2 separately from the monitoring performed by the overvoltage protection circuit of controller 43 described above, thereby enhancing safety. Second overvoltage protection circuit 43B may be omitted.
Fuse module 34 functions as an overvoltage-detecting fuse configured to blow upon detecting an overvoltage of secondary battery cells 1. Fuse module 34 includes two thermal fuses 34a and 34a connected in series to each other at a connection point and heating resistor 34b with one end connected to the connection point of thermal fuses 34a. The heating resistor generates heat upon being energized to cause thermal fuses 34a to blow. Heating resistor 634b is controlled by controller 43 and second overvoltage protection circuit 43B. For example, a resistance-heating switching element, such as a MOSFET, may be connected to heating resistor 634b so as to cause heating resistor 634b to work. In this case, the other end of the resistance-heating switching element may be connected to a conductive path on the ground side or, alternatively, an intermediate potential of battery unit 2 depending on a required drive voltage, a withstand voltage, or the like.
Lead member 50 is connected between fuse module 34 and battery-side output 21H. Lead member 50 is detachable from circuit unit 3. Detachment of lead member 50 from circuit unit 3 electrically separates fuse module 34 as shown in
Fuse module 34 disposed in charging-discharging path CP is mounted on circuit board 40. Lead member 50 connects between fuse module 34 and discharging path DP on circuit board 40. Lead member 50 may be implemented by a lead wire or metal bus bar.
In the case where the overvoltage-detecting fuse has a large size for passing a large current, a fuse module including the overvoltage-detecting fuse may be prepared as a separate member, instead of being mounted on the circuit board. For example, the fuse module may constitute a unit, such that the overvoltage-detecting fuse is accommodated in a case. The present invention is also applicable to even this case, so that lead member 50 is used to connect between circuit board 40 and fuse module 34. For example; in the example of
Lead member 50 is not limited to a bus bar, and may be implemented by a flexible member, such as, a wire clip or a lead wire with a connector. Fuse module 34 may be mounted on the circuit board. In this case, lead member 50 is effectively configured with a flexible member being easily attached and detached. The term “detachable” as referred to herein not necessarily means that lead member 50 can be completely and physically detached but means that lead member 50 is only required to be able to be temporally in a mode of physically intercepting the energization. For example, in the case of use of the lead wire or wire clip described above, while fixing one end thereof to one side of the fuse module or battery-side output, the other end thereof, as being a free end, is respectively coupled to the other side of the fuse module or battery-side output, with a clip, a ring crimp terminal, a connector, or the like by means of engaging, locking, clipping, inserting and removing, screwing, or the like. Alternatively, one end of the lead wire is fixed, and the other end is locked in such as a notch of the lead plate. Alternatively, a switch may be utilized in order to physically intercept the energization.
Hereinafter, a method of manufacturing the power supply device will be described. First, while detachable lead member 50 is detached, circuit unit 3 is connected to battery unit 2. For example, as shown in
In the present invention, other than the detachable configuration of lead member 50 for connecting between fuse module 34 and battery-side output 21H, the fuse module per se may be detachable. This configuration is shown in the circuit diagram illustrated in
A power supply device and a method of manufacturing thereof according to the present invention are preferably used as a backup power-supply device mountable in a power supply module of a computer server. In addition, it can appropriately be used in applications including backup power-supply devices of wireless base stations for mobile phones and the like, storage power supplies for use in households and plants, storage power devices combined with solar cells, e.g., power supplies for streetlights, and backup power supplies for traffic lights. The applications also include power supplies for, such as, plug-in hybrid electric vehicles switchable between an EV-running mode and an HEV-running mode, hybrid electric vehicles, and electric vehicles.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-013123 | Jan 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/001893 | 1/20/2022 | WO |
