HIGH POWER BATTERY/CAPACITOR MODULE

A high power battery/capacitor module is revealed. The high power battery/capacitor module includes a box, electrolyte solution, cells and a heat exchanging device. A chamber in the box is connected to the heat exchanging device to form a closed fluid circulation space. The electrolyte solution is filled into the chamber and the cells are arranged at the chamber of the box. The cells are immersed into and electrically insulated from the electrolyte solution. The electrolyte solution is cooled down by the heat exchanging device after being drawn away from the chamber and then delivered back to the chamber circularly. The high power battery/capacitor module further includes an automatic device for detecting and balancing concentrations of ions in the electrolyte solution. Thus the present battery/capacitor module solves the problems caused by heat generated during charging/discharging and extends service life of the battery/capacitor system by using electrolyte solution as coolant.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a battery/capacitor module, especially to a high power battery/capacitor module using electrolyte solution as coolant and involved in temperature control of secondary batteries.

Description of Related Art

In order to eliminate pollution (such as air pollution) caused by fossil fuel vehicles that use petrol or diesel, the trends of electric vehicles (EV), hybrid electric vehicles (HEV), and Plug-in HEV in near future are inevitable. Generally, a power battery used in vehicles includes a plurality of battery cells. The most common battery cell used is lithium ion battery (LIB). A plurality of packed cells is connected in series/parallel and then packed into a battery module/battery pack. The number of the battery modules/battery packs used depends on the power the vehicle requires. These battery modules/battery packs include thousands of battery cells.

One of the inevitable technical problems of the electric vehicles is heat generated during charge/discharge cycles of the power battery. The temperature is a key factor that affects service life and safety of the power battery. The battery overheating accelerates side reactions inside the battery and shortens the service life. In the worst case, the battery starts a thermal runaway that causes safety problems such as fire or explosions. The optimal operating temperature of the lithium ion battery is ranging from 25 degrees Celsius (° C.) to 40° C. Thus thermal management of the power battery has become one of the key research topics.

A high power battery and/or capacitor system is required by many applications such as electric vehicles. There is no other way to solve the problems associated with heat now except using cooling medium such as air, liquid or solid around the packed battery and/or capacitor unit.

The temperature control of lithium ion batteries can be achieved by various ways including air-cooling, fluid-cooling and PCM (phase change material)-cooling. Refer to US pat. App. No. 20110059347, a battery module with an air cooling type heat exchange member is revealed. A plurality of heat dissipation members is disposed in two or more interfaces between respective plate-shaped battery cells. Air passed through the heat dissipation members is used as coolant. Refer to Chinese Pat. Pub. No. CN202076386U, a battery temperature management system revealed. The battery temperature management system includes a battery pack, a heat exchanging system and a temperature control device. The heat exchanging system consists of a heat exchanger, a cooling liquid circulating pipeline, and refrigerant circulating pipeline. The battery is heated or cooled by heat exchange in the system and the medium used is cooling liquid, instead of air. Refer to US Pat. App. No. 20100279154, battery systems, battery modules and method for cooling a battery module are revealed. A phase change material is used as a coolant for heat dissipation of the battery. Basically the coolant or the refrigerant is the same as that used in the cooling system of the compressor and the condenser such as ethylene glycol (coolant), or R-11 and R-134A (refrigerants).

The above prior arts use cooling modules built outside the battery/capacitor module. These prior arts either improve the cooling modules around the battery/capacitor module or focus on the use of different materials for cooling plates or heat dissipation parts outside the battery/capacitor module. The battery/capacitor module and the cooling system are separated from each other in these patents and the cooling system of the battery doesn't work effectively. The lithium ion battery is composed of an anode (such as graphite), a cathode (such as lithium), electrolyte, and a separator. Most of the electrolyte in the battery is in the liquid form, also called electrolyte solution. In order to prevent oxidation and moisture, the electrode, the electrolyte, and the separator required are mounted in a permanently-sealed pack. The problem lies in that the packing material reduces thermal conduction and there is no direct heat transfer between the electrolyte solution and the air outside. All of the above patents have tried to reduce temperature outside the battery module/battery pack.

Thus there is room for improvement and there is a need to provide a novel battery/capacitor module.

SUMMARY OF THE INVENTION

Therefore it is a primary object of the present invention to provide a high power battery/capacitor module that solves the problems caused by heat generated during charging/discharging process of the high-power battery/capacitor module.

In order to achieve the above object, a high power battery/capacitor module according to the present invention includes a box, electrolyte solution, unpacked cells and a heat exchanging device. The box can be a rigid container or a flexible container. The box consists of a chamber therein, an inlet and an outlet, both communicated with the chamber. The electrolyte solution is filled in the chamber while the unpacked cells are arranged at the chamber and are immersed in the electrolyte solution. A first electrode set outside the box is electrically connected to positive electrodes of the cells and a second electrode disposed outside the box is electrically connected to negative electrodes of the cells. The heat exchanging device is connected to both the inlet and outlet of the box. A closed fluid circulation space is formed by the heat exchanging device in combination with the chamber. The electrolyte solution drawn from the chamber through the outlet is passed through the heat exchanging device to be cooled down and then delivered back to the chamber through the inlet circularly. Thus the unpacked cells are cooled inside by using the electrolyte solution as coolant. Therefore the present high power battery/capacitor module can be used without suffering problems caused by heat generated during charging/discharging.

The high power battery/capacitor module according to the present invention further includes an automatic device for balancing concentrations of ions which detects charge carrier/ion concentration in the chamber. The same electrolyte solution at higher concentrations is filled into the chamber or the heat exchanger automatically once the detection result shows that the ion concentration is lower. Thus the ion concentration around the electrodes of the unpacked cells remains stable. The degradation of cell capacity and shorter cell cycle caused by reduced lithium ions can be minimized. The service life of the battery/capacitor module is further extended.

The high power battery/capacitor module of the present invention further includes a charger that is electrically connected to an external power source, the first electrode and the second electrode. The cells are charged by the charger using power from the external power source.

The heat exchanging device is composed of a heat exchanger and a pump that are connected to the inlet and the outlet of the box respectively by pipelines. The electrolyte solution is drawn from the chamber through the outlet to be passed through the heat exchanger for temperature reduction and then is returned to the chamber through the inlet circularly by the pump.

The heat exchanging device is disposed on a charging pile that includes a charging plug. A first fluid connector and a second fluid connector are set on the charging plug. The first fluid connector and the second fluid connector are connected to the inlet and the outlet of the box respectively. A heat transfer medium inlet and a heat transfer medium inlet outlet on the heat exchanger of the heat exchanging device are connected to the first fluid connector and the second fluid connector of the charging plug respectively.

It is another object of the present invention to provide a high power battery/capacitor module for vehicles and a charger thereof.

In order to achieve the above object, a high power battery/capacitor module for vehicles and a charger thereof according to the present invention includes a box, electrolyte solution, unpacked cells, a heat exchanging device and a charger. The box can be a rigid container or a flexible container. The box not only has a chamber therein but also includes an inlet and an outlet that are communicated with the chamber. The chamber is filled with the electrolyte solution while the unpacked cells are mounted in the chamber of the box and are immersed into the electrolyte solution. A first electrode disposed outside the box is electrically connected to positive electrodes of the cells and a second electrode set outside the box is electrically connected to negative electrodes of the cells. The heat exchanging device is connected to both the inlet and outlet of the box and working together with the chamber to form a closed fluid circulation space. The electrolyte solution drawn from the chamber through the outlet is passed through the heat exchanging device to be cooled down and then delivered back to the chamber through the inlet in a circular manner. The charger is electrically connected to an external power source, the first electrode and the second electrode. The cells are charged by the charger using power from the external power source.

The heat exchanger is disposed on a front side of the vehicle for reducing temperature of the electrolyte solution by air-cooling or water-cooling solution. Then the cooled electrolyte solution is delivered back to the chamber through the inlet of the box.

The heat exchanging device is disposed on a charging pile that includes a charging plug. A first fluid connector and a second fluid connector are set on the charging plug. The first fluid connector and the second fluid connector are connected to the inlet and the outlet of the box respectively. A heat transfer medium inlet and a heat transfer medium inlet outlet on the heat exchanger of the heat exchanging device are connected to the first fluid connector and the second fluid connector of the charging plug. Thereby problems caused by heat generated during charging/discharging process of the high power battery/capacitor module can be solved when the vehicle hooks up to the charging pile and gets charged.

The high power battery/capacitor module for vehicles and a charger thereof according to the present invention further includes an automatic device for balancing concentrations of ions that detects charge carrier/ion concentration in the chamber. The same electrolyte solution at higher concentrations is filled into the chamber or the heat exchanger automatically once the detection result shows that the ion concentration is lower.

The automatic device for balancing concentrations of ions of the present invention is composed of a detector used for detecting ion concentration of the electrolyte solution in the chamber, a first container for storage of electrolyte solution with high concentration of ions, a second container in which electrolyte solution with low concentration of ions is stored, a distributor that is connected to the first container, the second container and the chamber, and the control circuit electrically connected to the detector and the distributor. The electrolyte solution with high concentration of ions in the first container and the electrolyte solution having low concentrations of ions in the second container can be optionally delivered and filled into the chamber by the distributor. According to detection results of the detector, the electrolyte solution with high concentration of ions in the first container or the electrolyte solution with low concentration of ions in the second container is delivered and filled into the chamber by the distributor under control of the control circuit.

The charger is arranged at the charging pile and is electrically connected to mains electricity that is used as an external power source.

The charger is set on the vehicle and electrically connected to an alternator of the vehicle. Thus the charger can use power from the alternator that works as an external power source.

The present invention features on that the electrolyte solution is used as coolant in the high power battery/capacitor module. The unpacked cells (composed of a cathode/a separator/an anode) are mounted in the chamber of the box and the electrolyte solution used as coolant is delivered into and out of the chamber by sealed hoses/tubes. During charging and discharging cycles, heat generated by the cells is sent to the heat exchanger outside together with the electrolyte solution for dissipation. Thus problems caused by heat generated upon charging and discharging operations of the high power battery/capacitor module can be solved and the service life of the battery/capacitor system is prolonged. Moreover, the automatic device for balancing concentrations of ions makes the concentration of ions around the electrodes of the unpacked cells stable. The degradation of cell capacity and shorter cell cycle caused by reduced lithium ions can be minimized. The service life of the battery/capacitor module is also extended.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Refer toFIG. 1a high power battery/capacitor module according to the present invention includes a box10, electrolyte solution20, a plurality of unpacked cells30and a heat exchanging device40.

The box10is composed of a chamber11therein, an inlet12and an outlet13. The inlet12and the outlet13are communicated with the chamber11. The box10can be a rigid container or a flexible container.

The electrolyte solution20is filled into the chamber11through the inlet12and is drained from the chamber11through the outlet13.

The unpacked cells30(each of which is generally composed of a cathode, a separator and an anode) are connected in series and/or in parallel and mounted in the chamber11of the box10. The cells30are immersed into the electrolyte solution20while positive electrodes of the cells30are electrically connected to a first electrode21outside the box10and negative electrodes of the cells30are electrically connected to a second electrode22outside the box10.

The heat exchanging device40is connected to both the inlet12and outlet13of the box10. A closed fluid circulation space is formed by the heat exchanging device40together with the chamber11. The electrolyte solution20in the chamber11is carried out through the outlet13, passed through the heat exchanging device40to be cooled down, and then delivered back to the chamber11through the inlet12circularly.

The heat exchanging device40consists of a heat exchanger41and a pump42that are connected to the inlet12and the outlet13of the box10respectively by pipelines. Heat generated during charging/discharging of the cells30is absorbed by the electrolyte solution20. The electrolyte solution20with the heat absorbed is drawn from the chamber11through the outlet13, passed through the heat exchanger41for temperature reduction, and then the cooled electrolyte solution20is sent back to the chamber11through the inlet12by the pump42in a circular manner. The electrolyte solution20used as coolant can also be introduced into and removed from the chamber11by sealed hoses/tubes. During charging and discharging, heat generated by the cells30is delivered to the heat exchanger41located outside the chamber11together with the electrolyte solution20. Thus the problems caused by heat occurred upon charging and discharging operations of the high power battery/capacitor module can be solved and the service life of the battery/capacitor system is extended.

Refer toFIG. 2, another embodiment of a high power battery/capacitor module of the present invention further includes an automatic device for balancing concentrations of ions50that detects the concentrations of ions in the electrolyte solution20. Once the detection result shows that the ion concentration is lower, the same electrolyte solution20at higher concentrations is filled into the chamber11or the heat exchanger41automatically. Thus the concentration of ions around the electrodes of the cells30remains stable. The degradation of cell capacity and shorter cell cycle caused by reduced lithium ions can be minimized. The service life of the battery/capacitor module is also prolonged. The automatic device for balancing concentrations of ions50consists of a first container51used for storage of electrolyte solution with high concentration of ions, a second container52in which electrolyte solution with low concentration of ions is stored, a detector53that detects ion concentration of the electrolyte solution20, a distributor54, and a control circuit55. The distributor54is connected to the first container51, the second container52and the chamber11/or the heat exchanger41. The electrolyte solution with high concentration of ions in the first container51and the electrolyte solution having low concentrations of ions in the second container52can be optionally delivered and filled into the electrolyte solution20by the distributor54. The control circuit55is electrically connected to the detector53and the distributor54. According to detection results of the detector53, the electrolyte solution with high concentration of ions in the first container51or the electrolyte solution with low concentration of ions in the second container52is delivered and filled into the electrolyte solution20by the distributor54under control of the control circuit55. For example, replenishment, balance and regulation of ions in the electrolyte solution20can be done through the heat exchanger41or the chamber11connected to the distributor54by pipelines.

Refer toFIG. 3, a further embodiment of a high power battery/capacitor module according to the present invention further includes a charger60that is electrically connected to an external power source P, the first electrode21and the second electrode22. The cells30are charged by the charger60using power from the external power source.

A high power battery module of the present invention can be applied to vehicles. In an embodiment of the present invention, a plurality of cells30is mounted into a chamber11. After the cells30being connected in series and/or in parallel, positive electrodes of the cells30are electrically connected to a first electrode21and negative electrodes of the cells30are electrically connected to a second electrode22so as to form a battery module (also called battery pack). In general, a vehicle may need a plurality of battery modules/battery packs. Inlets12and outlets13of these battery modules/battery packs are connected to the heat exchanging device40by pipelines to form a closed fluid circulation space. Thus the cells30can be cooled down.

Moreover, the cell30in the embodiment of the present invention can be replaced by high power capacitor that stores electrical energy. Thus the present invention can be further applied to other equipment that requires high power electricity.

Refer toFIG. 4, a further embodiment is revealed. In this embodiment, the box10is a rigid container made from plastic or metals. A first electrical connector interface14is disposed on an outer side of the box10and is electrically connected to at least one first electrode21and at least one second electrode22. In this embodiment, there are two sets of the first electrode21and two sets of the second electrode22arranged at the first electrical connector interface14and the first electrical connector interface14can be used as a charging interface and power output interface simultaneously. A charger60is electrically connected to one of the two sets of the first electrode21and one of the two sets of the second electrode22on the first electrical connector interface14by a first cable61for charging the cells30. A power load (such as an electric motor in vehicles) is electrically connected to the other set of the first electrode21and the other set of the second electrode22on the first electrical connector interface14by a second cable62for using power from the cells30.

In an embodiment applied to vehicles, the heat exchanger41can be disposed on a front side of cars or electric vehicles for reducing temperature of the electrolyte solution20by air-cooling or water-cooling solution, as shown inFIG. 6. Then the cooled electrolyte solution20is delivered back to the chamber11through the inlet12. Heat generated during charging/discharging of the cells30is dissipated by circulation of the electrolyte solution20for cooling and temperature control of the cells30.

Furthermore, in a further embodiment shown inFIG. 5, the heat exchanging device40is disposed on a charging pile A that includes a charging plug70. The charging plug70is arranged with a first fluid connector71and a second fluid connector72that are connected to the inlet12and the outlet13of the box10respectively. The charging plug70is usually connected to the inlet12and the outlet13of the box10through a charging interface63located on an outer surface of the electric vehicle, as shown inFIG. 4. A first quick connector64able to connect to the first fluid connector71and a second quick connector65able to connect to the second fluid connector72are both set on the charging interface63. The first quick connector64and the second quick connector65are connected to the inlet12and the outlet13by a pipeline641and a pipeline651respectively. A heat transfer medium inlet and a heat transfer medium inlet outlet on the heat exchanger41of the heat exchanging device40on the charging pile A are connected to the first fluid connector71and the second fluid connector72of the charging plug70of the charging pile A. The first fluid connector71and the second fluid connector72are preferably quick connectors. Thereby the cells30are cooled by the heat exchanging device40on the charging pile A when the vehicle is charged by the charging pile A.

In an embodiment of the present invention, the charger60is set on the vehicle and electrically connected to an alternator of the vehicle. Thus the charger60can use power generated by the alternator that works as an external power source.

In a further embodiment, the charger60is set on the charging pile A and is electrically connected to mains electricity that is used as an external power source. The charging plug70further includes a charging terminal73that can be electrically connected to the charging interface63on the outer surface of the electric vehicle. Thus the cells30are charged by the external power source of the charging pile A.