Patent Application
20160013510
The present disclosure relates to a battery system having a plurality of micro-batteries.
Generally, the performance of electric and hybrid vehicles is limited by the drawbacks of conventional battery technology. Conventional batteries, such as Li-ion batteries, face several significant challenges in terms of performance within the areas of capacity, charging time, cycling life, cost, etc. For instance, several hours are needed to fully charge the type of battery currently used in electric vehicles. Further, as an example of another drawback, the battery pack of an electric or hybrid vehicle is designed with 50% over-capacity. Such over-capacity cannot be directly used but is held in reserve to accommodate anticipated battery capacity degradation over the life of the vehicle. As a result, such over-capacity significantly increases the weight of the battery pack and reduces the driving range of the vehicle. Even further, when designing the battery pack for electric and hybrid vehicles, significant engineering resources are required to design a battery pack that has a customized size and shape. As a result, generally, batteries packs are vehicle-specific and cannot be shared between vehicles. Moreover, the battery pack may also require sophisticated cooling systems, which further increases the overall cost of battery pack development. A need, therefore, exists for a battery system that addresses the drawbacks of conventional battery technology.
It is an objective of the present disclosure to provide a battery system that reduces charging time and overcomes the disadvantages due to battery capacity degradation.
In an aspect of the present disclosure, a bubble battery system includes a plurality of micro-batteries, fluid media, a battery media tank, a power extractor, and an electric load. Each micro-battery is repeatedly rechargeable and the fluid media immerses the micro-batteries. The tank stores the fluid media and the micro-batteries. The power extractor is fluidly connected to the tank and extracts electric power that is stored inside the micro-batteries while the fluid media and the plurality of micro-batteries flow through the power extractor. The electric load is electrically connected to the power extractor and driven by the electric power extracted by the power extractor.
Accordingly, the electric power is discharged from the micro-batteries while the fluid media and the micro-batteries flow through the extractor. After the micro-batteries are discharged, the discharged micro-batteries within the fluid media may be removed and replaced with fluid media that contains fully charged micro-batteries. Similar to refilling a fuel tank of a vehicle with gasoline or changing a vehicle's engine oil, discharged micro-batteries may be quickly replaced relative to the time required to fully charge a conventional battery pack of an electric or hybrid vehicle.
Further, individual damaged micro-batteries or micro-batteries that have reached their serviceable life may be individually replaced with new micro-batteries. As a result, the bubble battery system may be designed with far less over-capacity compared to a conventional battery pack. Thus, the total weight and size of the bubble battery system may be reduced, which increases driving range and decreases cost.
The disclosure, together with additional objectives, features and advantages thereof, will be best understood from the following description, the appended claims and the accompanying drawings, in which:
The bubble battery system according to the present embodiment will be described with reference to the drawings. The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It is to be noted that, in the present embodiment, the bubble battery system is applied to an electric vehicle.
In the present embodiment, each micro-battery 12 is a self-contained battery that may be repeatedly charged and discharged. As illustrated in
The battery shell 24 is made from a non-conductive material (i.e., an electric insulator) such as plastic. The battery shell 24 has a spherical shape that defines the external shape of the micro-battery 12. It should be understood to one of ordinary skill in the art that the shape of the battery shell 24 is not limited to only spherical shapes and may be formed in other shapes such as an ovular shape or the like. An inner liner (not shown) is provided within the battery shell 24 and covers an inner wall of the battery shell 24 to create a seal between an inside and an outside of the battery shell 24. The battery shell 24 seals air inside the battery shell 24, which may allow the micro-battery 12 to be buoyant in the inert fluid 14.
The battery portion 26 is enclosed inside the battery shell 24 and stores an electrical charge. Similar to a Li-ion rechargeable battery, the battery portion 26 is a rechargeable battery that may be repeatedly discharged and charged. However, it should be understood to one of ordinary skill in the art that the battery portion 26 is not limited to only Li-ion rechargeable battery technology and may include other electricity storage technologies.
The battery portion 26 may be recharged using wireless power transmission such as resonant magnetic induction. The first power transfer 28 may be a coil that wirelessly receives and/or transfers electric power. Through the first power transfer 28, the electric power may be charged into the micro-battery 12 from the power extractor 20 or discharged to the power extractor 20 from the micro-battery 12. The first power transfer 28 is attached to the inner wall of the battery shell 24 and electrically connected to the battery portion 26 by conductive wires 28a. Therefore, during recharging, electricity that is wirelessly received by the first power transfer 28 may be transferred to the battery portion 26. Similarly, during discharging, electricity stored in the battery portion 26 may be transferred from the battery portion 26 and discharged through the first power transfer 28.
The battery magnet 30 is positioned in the center of the first power transfer 28 (i.e., the center of the coil) and is attached to the inner wall of the battery shell 24. The battery magnet 30 is magnetized to have, for example, an S-pole to attract an extractor magnet 56 of the power extractor 20 as described below. The battery magnet 30 is configured to align the micro-battery 12 so that the micro-battery 12 can be in a position with respect to the extractor magnet 56 such that the electric power may transfer between the micro-battery 12 and the power extractor 20.
The inert fluid 14 may be a liquid such as water, hydraulic fluid, or the like. In other words, a liquid having inert properties may be adopted as the inert fluid 14. Water may be preferred as the inert fluid 14 in terms of cost-effectiveness and availability. As shown in
Further, the inert fluid 14 may serve as a heat transfer media (i.e., heat exchanger) for the micro-batteries 12. The inert fluid 14 exchanges heat generated in the micro-batteries 12 and cools the micro-batteries 12 by exchanging the heat. The heat exchanged by the inert fluid 14 may be used for heating a cabin room, for example.
The tank 16 includes an exterior body 44 having an inside space and a separator 38 separating the inside space of the exterior body 44 into two volumes, as shown in
The separator 38 divides the inside space of the exterior body 44 into a powered space 46 and a depowered space 48. The powered space 46 stores charged micro-batteries 12. On the other hand, the depowered space 48 stores discharged micro-batteries 12. The separator 38 is formed as a semipermeable membrane that allows the inert fluid 14 to pass between the powered space 46 and the depowered space 48. However, micro-batteries 12 cannot pass through the separator 38. As such, the inert fluid 14 flowing into the depowered space 48 is allowed to pass through the separator 38 and collect into the powered space 46 such that the inert fluid 14 may be reused. Further, the separator 38 may be flexible to adjust to the changing volumes of charged and discharged micro-batteries 12 within the powered space 46 and the depowered space 48. Even further, the depowered space 48 may be positioned above the powered space 46 since discharged micro-batteries 12 may be more buoyant than charged micro-batteries 12. As a result, the positioning of the powered space 46 and the depowered space 48 may accommodate the difference in buoyancies of the charged and discharged micro-batteries 12. Further, the difference in buoyancies may be used to sort and transfer the charged and discharged micro-batteries 12.
The powered space 46 is fluidly connected to the power extractor 20 through an upstream pipe 50 and the depowered space 48 is fluidly connected to the power extractor 20 through a downstream pipe 52. The upstream pipe 50 and the downstream pipe 52 constitute the fluid circulation path 42 for the power fluid.
The pump 18 is fluidly connected to the upstream pipe 50 and positioned between the power extractor 20 and the tank 16. The pump 18 suctions the power fluid within the powered space 46 and supplies the power fluid to the power extractor 20. The pump 18 is controlled by a controller (not shown) and the controller adjusts a supply flow rate of the power fluid from the pump 18 according to a power demand of the vehicle (e.g., an acceleration amount requested by a driver). That is, the controller controls the pump 18 to increase the supply flow rate of the power fluid as the power demand of the vehicle increases.
As shown in
A plurality of second power transfers 54 are attached on an outer surface of the power extractor 20. The second power transfers 54 are arranged at substantially equal intervals and positioned entirely on the outer surface of the power extractor 20. Each second power transfer 54 may be a coil that wirelessly transfers the electric power. The second power transfer 54 receives and/or transfers the electric power using the wireless transmission technology to/from the first power transfer 28.
When the micro-battery 12 discharges, the second power transfer 54 receives the electric power from the micro-battery 12 through the first power transfer 28. Whereas, when the micro-battery 12 charges, the second power transfer 54 transfers the electric power into the micro-battery 12 through the first power transfer 28.
Each second power transfer 54 has an extractor magnet 56 (i.e., second alignment part). The extractor magnet 56 is positioned in the center of the second power transfer 54 (i.e., the center of the coil) and attached to the outer wall of the power extractor 20. The extractor magnet 56 is magnetized to have a pole opposite to that of the battery magnet 30 (i.e., an N-pole in the present embodiment). Thus, the extractor magnet 56 and the battery magnet 30 are magnetically attracted to each other. As shown in
As described above, the electric power of each micro-battery 12 is extracted by the power extractor 20 while the power fluid flows through the power extractor 20. When the power fluid passes through the power extractor 20, the electric power of each micro-battery 12 is fully extracted and the discharged micro-batteries 12 are stored in the depowered space 48.
The electric motor 22 functions as an electric load powered by the bubble battery system 10. The electric motor 22 is electrically connected to the power extractor 20 and the electric power extracted by the power extractor 20 is supplied to the electric motor 22. The electric vehicle EV is propelled by the electric motor 22 powered by the electric power supplied from the power extractor 20.
It should be noted that the electric power extracted by the power extractor 20 may be stored in the fixed storage device 32. The electric power stored in the fixed storage device 32 is available at any time. For example, the electric power stored in the intermediary onboard battery can be used to power auxiliary vehicle systems or devices when power is not being extracted by the power extractor 20.
The bubble battery system 10 provides for the refilling of the power fluid (i.e., the micro-batteries 12). More specifically, the power fluid stored in the depowered space 48 of the tank 16 that contains the discharged micro-batteries 12 may be removed. Then, new power fluid that contains the fully charged micro-batteries 12 is refilled into the powered space 46 of the tank 16. In other words, the power fluid that has already been discharged can be replaced with the power fluid that is fully charged.
For refilling the power fluid, a refilling device 58 may be used in a manner illustrated in
In addition, the refilling device 58 may be connected to an external power source 66, as shown in
Similar to gas stations along side of the road, the refilling device 58 may be installed at a commercial facility such that power fluid is readily available to consumers. The refilling device 58 may be also installed in a home for personal use. Further, the refilling device 58 may be integrated with alternative or renewable energy systems (e.g., solar, wind, geothermal, hydroelectric, etc.) to reduce energy costs and environmental impact.
The bubble battery system 10 may be also charged without refilling the power fluid through the refilling device 58. As shown in
For example, as shown in
The bubble battery system 10 may also include a wireless power transmitter 68 that is located outboard of the electric vehicle EV for charging the micro-batteries 12. As shown in
(1) According to the bubble battery system 10 in the present embodiment, the electric vehicle EV does not depend on a conventional battery that is fixed to the vehicle. That is, when the bubble battery system 10 is discharged, the electric vehicle EV can replace the micro-batteries 12 discharged with those charged by refilling the power fluid. Therefore, vehicle performance such as range, fuel consumption, or the like, can be increased as battery capacity of each micro-battery 12 improves according to advancements in micro-battery technology (i.e., batteries smaller in size and having higher energy density). In other words, as micro-batteries become smaller and capacity improves over time, vehicle performance will also improve. As a result, the bubble battery system 10 can use newly developed and higher capacity micro-batteries 12. Thus, an owner may not feel the need to replace a bubble battery powered electric vehicle EV as often (i.e., relative to conventional gasoline, hybrid, or electric vehicles), which expands the usable life of the vehicle. This is in contrast to conventional gasoline, hybrid, or electric vehicles, where the relative performance of the vehicle is fixed or diminishes relative to advancements in vehicle technology.
(2) The discharged micro-batteries 12 can be replaced with the micro-batteries 12 that are fully charged by refilling the power fluid through the refilling device 58. Therefore, the power fluid can be refilled in minutes, similar to petroleum-based fuels such as gasoline. Thus, in contrast to the amount of time required to charge a conventional electric vehicle, a bubble battery powered electric vehicle EV may be charged quickly.
Further, the bubble battery system 10 can be charged while onboard the electric vehicle EV by using existing battery charging technology (i.e., plug-in charging). Therefore, the bubble battery system 10 can be charged while the electric vehicle EV is not used. For example, the electric vehicle EV (i.e., the bubble battery system 10) can be charged using a home power source during night time hours when electricity costs are low.
Even further, the refilling device 58 may be used as a home energy storage device that charges the micro-batteries 12 using low or no cost energy sources. As such, the amount of power purchased at peak hours (i.e., highest cost) is reduced. Moreover, excess energy stored by the refilling device 58 may be sold back to the power grid.
(3) Batteries currently used in electric vehicle EVs are designed with up to 50% over-capacity to accommodate for battery capacity degradation over time. Thus, the weight and the size of conventional batteries are increased, resulting in reducing the driving range and increasing the cost. However, since the bubble battery system 10 can replace old micro-batteries 12 with newer micro-batteries 12 and no consideration of the battery capacity degradation is needed, each micro-battery 12 need not be designed with over-capacity. Thus, the weight and the size of the total micro-batteries 12 can be decreased compared to conventional batteries, which can increase the driving range and decrease cost.
Further, energy density of the power fluid can increase according to the number of micro-batteries 12 inside the power fluid. Therefore, the energy density of the bubble battery can be higher than conventional batteries by increasing a number of the micro-battery 12 per unit amount of the power fluid.
(4) As described above, the bubble battery system 10 transfers the electric power between the micro-batteries 12 and the power extractor 20 by wireless transfer technology. Therefore, copper wiring is not needed to connect the micro-batteries 12 and the power extractor 20, and thus, the amount of the copper wiring used in the bubble battery system 10 can be reduced, resulting in decreased environmental costs.
(5) The inert fluid 14 acts as a heat dissipation mechanism to cool the micro-batteries 12. Therefore, there is no need for a separate cooling fluid to cool the micro-batteries 12. Further, heat extracted from the micro-batteries 12 may be used to heat the interior cabin of the electric vehicle EV.
In the present embodiment, water is adopted as the inert fluid 14. Since water has non-explosive and non-toxic properties, damage to the vehicle is unlikely to occur even if the bubble battery system 10 is damaged.
(6) The fluid properties of the inert fluid 14 and the small size of the micro-battery 12 allow flexibility in the design of the tank 16. Therefore, the bubble battery system 10 may be used with a variety of vehicles, i.e., the tank does not have shape constraints as compared with conventional batteries. Further, with the design flexibility, the shape of the tank 16 may be molded to improve the safety of the bubble battery system 10.
(7) Since each micro-battery 12 has the battery shell 24 covering the battery portion 26, each micro-battery 12 independently exists in the inert fluid 14 without any metal contact with other components. Therefore, in the event of an accident when one or more micro-batteries 12 are damaged, the damage is contained within the battery shell resulting in minimal impact on other undamaged micro-batteries 12 or components. Further, the damaged micro-batteries 12 can be easily removed from the electric vehicle EV by emptying the tank 16 of the existing damaged and undamaged micro-batteries 12 and refilling the tank 16 with only undamaged micro-batteries 12.
In the above-described embodiment, the bubble battery system 10 is applied to a personal vehicle. However, it should be understood to one of ordinary skill in the art that the bubble battery system 10 may be applied to commercial, recreational, and heavy-duty type vehicles. For examples, the bubble battery system 10 may be applied to a farm tractor 70, as shown in
In farming applications, range anxiety prevents farmers from switching to electrically driven tractors from conventional tractors. As described above, however, the bubble battery system 10 can be recharged in a similar amount of time as the time required for the refilling of a conventional gasoline or diesel powered vehicle. Therefore, a farm tractor 70 utilizing the bubble battery system 10 can be recharged by refilling the power fluid, thereby eliminating the recharging time and range anxiety concerns of vehicles powered by conventional batteries.
Moreover, the bubble battery system 10 may be applied to any device that utilizes electricity as a power source.
In the above-described embodiment, the micro-battery 12 has a spherical shape, but it should be understood to one of ordinary skill in the art that the micro-battery 12 may have a shape other than a spherical shape. For example, the micro-battery 12 may have an oval shape.
In the above-described embodiment, the electric power is wirelessly transferred between the micro-battery 12 and the power extractor 20 through the first power transfer 28 and the second power transfer 54. However, it should be understood to one of ordinary skill in the art that the electric power may be conductively transferred through a physical electrical connection between the micro-battery 12 and the power extractor 20.
In the above-described embodiment, the power extractor 20 has a cylindrical shape and extends linearly along a flow path of the power fluid. However, the power extractor 20 may not be limited to this configuration. For example, the power extractor 20 may have a polygonal tubular shape or a curved cylindrical shape providing a curved flow path for the power fluid.
Further, in the above-described embodiment, the pump 18 is provided on an upstream side of the power extractor 20. Alternatively, the pump 18 may be provided on a downstream side of the power extractor 20 or on both upstream and downstream sides of the power extractor 20.
