Battery system with high energy density and high power density

Abstract

The utility model discloses a battery system with both high energy density and high power density, which is characterized in that the battery system comprises a box body, cylindrical lithium batteries which are sequentially arranged along the transverse direction and the longitudinal direction are arranged in the box body, and a cylindrical lithium ion super capacitor is arranged in a gap between two adjacent rows of cylindrical lithium batteries; all the cylindrical lithium batteries are electrically connected to form a lithium ion battery system, and all the lithium ion super-capacitors are electrically connected to form a lithium super-capacitance system; the voltage of the lithium ion battery system is matched with that of the lithium super-capacity system, and the lithium ion battery system is connected with a battery management system. The utility model has the advantages that the space utilization rate can be improved, the thermal load of a single battery is reduced, and the system safety and stability can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy, and particularly to a battery system with both high energy density and high power density. Background Art

[0002] With the rapid development of the new energy vehicle industry, the market has put forward higher requirements for the energy density and power density of in-vehicle battery systems. The energy density is directly related to the driving range of electric vehicles, while the power density affects the acceleration performance and climbing ability. Therefore, the development of lithium battery systems with high energy density and high power density is crucial for new energy vehicles.

[0003] The solutions of the new energy vehicle industry in improving energy density and power density mainly focus on battery material innovation, battery structure optimization, and system integration design. The development of the new energy vehicle industry in battery structure optimization and system integration design mainly focuses on improving the energy density, power density of the battery, and the integration efficiency of the whole vehicle. At present, the new energy vehicle industry has made many innovations in the energy density of the battery system in terms of battery structure optimization and system integration design, such as CTP technology and CTC technology of CATL, and blade batteries of BYD, etc., but relatively little work has been done in improving the power density of the system.

[0004] Existing new energy vehicle battery systems face some challenges and disadvantages when pursuing high energy density and high power density. First of all, high-energy-density batteries often need to use thinner diaphragms and higher-energy cathode materials, which may reduce the thermal stability of the battery and increase safety risks. Secondly, in order to achieve high power density, the battery needs to have the ability of fast charging and discharging, which will cause the internal temperature of the battery to rise, affecting its life and performance. In addition, the improvement of power density may sacrifice energy density, because the increased parallel circuits and heat dissipation designs will occupy more space and increase weight, thus reducing the overall energy density. Therefore, it is necessary to find a balance between energy density and power density in battery design, while ensuring the safety, reliability, and economy of the battery. Summary of the Utility Model

[0005] Aiming at the deficiencies of the above-mentioned prior art, the technical problem to be solved by the utility model is: how to provide a battery system that can improve space utilization rate, reduce the thermal load of a single battery, and is beneficial to improving the safety and stability of the system.

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A battery system with both high energy density and high power density, characterized in that it includes a box body, and cylindrical lithium batteries are arranged in the box body in sequence along the transverse and longitudinal directions, and cylindrical lithium-ion supercapacitors are arranged in the gaps between two adjacent rows of the cylindrical lithium batteries; all the cylindrical lithium batteries are electrically connected to form a lithium-ion battery system, and all the lithium-ion supercapacitors are electrically connected to form a lithium supercapacitor system; the voltage of the lithium-ion battery system matches the voltage of the lithium supercapacitor system, and a battery management system is connected.

[0008] In the above structure, by cleverly arranging lithium-ion supercapacitors with a smaller diameter in the gaps between cylindrical lithium batteries, the efficient utilization of the space of the battery system is realized. This layout method not only maintains the volume energy density of the battery system, but also significantly improves the power performance of the system without increasing the extra volume. In addition, the lithium-ion battery system can be used for energy recovery and storage, and is responsible for providing long-term endurance; when driving smoothly or braking to recover energy, the lithium battery serves as the main energy exchange unit, responsible for energy storage and supply. The lithium supercapacitor system can be used for high-current output and provide instant high-power output ability. In occasions such as vehicle starting and accelerating that require high-current output, the lithium supercapacitor will quickly release energy to meet the high-power demand. Such a design not only improves the transient response ability of the battery system, but also significantly increases the cycle service life of the battery. At the same time, due to the excellent fast charge and discharge ability and high power density of the lithium supercapacitor, they play a role of power buffering in the battery pack, can effectively smooth the power fluctuation of the lithium battery under high-power demand, reduce the instantaneous load of the lithium battery, and thus extend its service life. In addition, the addition of the lithium supercapacitor disperses the power output, reduces the thermal load of a single battery unit, helps to achieve a more uniform temperature distribution, and thus improves the safety and stability of the entire system.

[0009] Further, the lithium-ion battery system and the lithium supercapacitor system are arranged in parallel and connected to the battery management system.

[0010] Further, the battery management system includes a lithium-ion battery management system and a lithium supercapacitor battery management system. The lithium-ion battery system is electrically connected to the lithium-ion battery management system, and the lithium supercapacitor system is electrically connected to the lithium supercapacitor battery management system.

[0011] Further, the diameter of the cylindrical lithium battery is 46mm, 60mm or 66mm; the diameter of the lithium-ion supercapacitor corresponds to 19mm, 24mm or 27mm.

[0012] Further, the box body includes a bottom plate, and the bottom plate is provided with limiting strips extending along the length direction or the width direction. A plurality of the limiting strips are arranged side by side at equal intervals, and accommodation grooves are formed between two adjacent limiting strips. A cooling plate extending along the length direction is arranged in the accommodation groove, and a cooling flow channel is arranged in the cooling plate. The cylindrical lithium batteries are sequentially arranged on the cooling plate in the accommodation groove; the lithium-ion supercapacitor is arranged between the gaps of the cylindrical lithium batteries and is located on the limiting strips.

[0013] Further, on the opposite sides of two adjacent limiting strips, there are positioning grooves that are oppositely arranged and arc-shaped. Two mutually opposite positioning grooves are combined into an accommodation cavity, and a plurality of the accommodation cavities are evenly arranged along the length direction of the limiting strip; the inner diameter of the accommodation cavity matches the diameter of the cylindrical lithium battery, and the cylindrical lithium battery is placed in the accommodation cavity.

[0014] Further, on two adjacent limiting strips, there are convex platforms extending towards the middle, and the convex platforms are located between two adjacent accommodation cavities; the cooling plate is erected on the convex platforms and forms a discharge cavity with the bottom of the accommodation groove; there is a discharge channel communicating with the discharge cavity between the cooling plate and the positioning groove or on the cooling plate, and the discharge channel corresponds to the position of the explosion-proof valve at the bottom of the cylindrical lithium battery.

[0015] Further, the positioning groove has a step protruding radially inwards, and the height of the step is the same as the height of the upper surface of the cooling plate.

[0016] Further, busbars are arranged at both ends in the length direction of the limiting strip, and a busbar flow channel is arranged in the busbar; both ends of the cooling plate are connected to the corresponding busbars, and the cooling flow channel is communicated with the busbar channel.

[0017] Further, a heat-conducting material is filled between the cooling plate and the cylindrical lithium battery.

[0018] In summary, the utility model has the advantages of being able to improve the space utilization rate, reduce the heat load of a single battery, and being beneficial to improving the safety and stability of the system. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the overall structure inside the box body.

[0020] Figure 2 It is a schematic diagram of the battery arrangement.

[0021] Figure 3 It is a schematic diagram of the arrangement of the bottom plate and the lithium-ion supercapacitor.

[0022] Figure 4It is a schematic structural diagram of a bottom plate and a cooling plate.

[0023] Figure 5 It is Figure 4 a partially enlarged structural schematic diagram in

[0024] Figure 6 It is a schematic structural diagram of a cooling plate and a bus bar plate. Specific embodiments

[0025] The following further elaborates on the present utility model in conjunction with embodiments.

[0026] During specific implementation: As Figures 1 to 6 shown, a battery system with both high energy density and high power density includes a box body 1. Inside the box body 1, cylindrical lithium batteries 2 are arranged in sequence along the transverse and longitudinal directions. A cylindrical lithium-ion supercapacitor 3 is arranged in the gap between two adjacent rows of the cylindrical lithium batteries 2; all the cylindrical lithium batteries 2 are electrically connected to form a lithium-ion battery system, and all the lithium-ion supercapacitors 3 are electrically connected to form a lithium supercapacitor system; the voltage of the lithium-ion battery system matches the voltage of the lithium supercapacitor system, and a battery management system is connected. In this embodiment, the lithium-ion battery system and the lithium supercapacitor system are arranged in parallel and connected to the battery management system.

[0027] During specific implementation, the lithium-ion batteries and the lithium supercapacitors can also be respectively connected in series and parallel, each forming an independent system, and each independently connected to the host or control unit to independently provide energy for the host or receive feedback. That is, the battery management system includes a lithium-ion battery management system and a lithium supercapacitor battery management system. The is electrically connected to the lithium-ion battery management system, and the is electrically connected to the lithium supercapacitor battery management system.

[0028] Specifically, in order to reasonably arrange the cylindrical lithium batteries 2 and the lithium-ion supercapacitors 3, the diameter of the cylindrical lithium batteries 2 can be selected as 46 mm, 60 mm, or 66 mm; correspondingly, the diameters of the lithium-ion supercapacitors 3 are respectively selected as 19 mm, 24 mm, or 27 mm.

[0029] In the above structure, by cleverly arranging lithium-ion supercapacitors with a smaller diameter in the gaps of cylindrical lithium batteries, the efficient utilization of the space of the battery system is achieved. This layout not only maintains the volumetric energy density of the battery system but also significantly improves the power performance of the system without increasing the extra volume. In addition, the lithium-ion battery system can be used for energy recovery and storage and is responsible for providing long-term endurance. When driving smoothly or braking to recover energy, the lithium battery serves as the main energy exchange unit and is responsible for energy storage and supply. The lithium supercapacitor system can be used for high-current output and provides instantaneous high-power output capabilities. In situations such as vehicle startup and acceleration that require high-current output, the lithium supercapacitor will quickly release energy to meet the high-power demand. Such a design not only improves the transient response ability of the battery system but also significantly increases the cycle life of the battery. At the same time, due to the excellent fast charge and discharge capabilities and high power density of the lithium supercapacitors, they play a role of power buffering in the battery pack, can effectively smooth the power fluctuations of the lithium battery under high-power demands, reduce the instantaneous load of the lithium battery, and thus extend its service life. In addition, the addition of lithium supercapacitors disperses the power output, reduces the thermal load of a single battery cell, helps for a more uniform temperature distribution, and thus improves the safety and stability of the entire system.

[0030] During implementation, the box body 1 includes a bottom plate 11. The bottom plate 11 is provided with a plurality of limiting strips 12 extending along the length direction or the width direction. The limiting strips 12 are arranged side by side at equal intervals. An accommodation groove is formed between two adjacent limiting strips 12. A cooling plate 13 extending along the length direction is arranged in the accommodation groove. A cooling flow channel is arranged in the cooling plate 13. The cylindrical lithium batteries 2 are sequentially arranged on the cooling plate 13 in the accommodation groove. A heat-conducting material is filled between the cooling plate 13 and the cylindrical lithium batteries 2. The lithium-ion supercapacitors 3 are arranged in the gaps between the cylindrical lithium batteries 2 and are located on the limiting strips 12. Opposite sides of two adjacent limiting strips 12 are provided with positioning grooves 14 that are oppositely arranged and arc-shaped. Two mutually opposite positioning grooves 14 are combined into an accommodation cavity. A plurality of the accommodation cavities are evenly arranged along the length direction of the limiting strips 12. The inner diameter of the accommodation cavity matches the diameter of the cylindrical lithium battery 2. The cylindrical lithium battery 2 is placed in the accommodation cavity. In this way, the cooling plate can provide a better cooling environment for the bottom of the cylindrical lithium battery and improve the heat dissipation of the battery system.

[0031] Specifically, there are bosses 15 extending towards the middle on two adjacent limiting strips 12, and the bosses 15 are located between two adjacent accommodating cavities; the cooling plate 13 is erected on the bosses 15 and forms a discharge cavity 16 with the bottom of the accommodating groove; there is a discharge channel communicating with the discharge cavity 16 between the cooling plate 13 and the positioning groove 14 or on the cooling plate 13, and the discharge channel corresponds to the position of the explosion-proof valve at the bottom of the cylindrical lithium battery 2. In this way, once the cylindrical lithium battery bursts open the explosion-proof valve due to a fault, the splashes will enter the discharge cavity through the discharge channel and diffuse outwards, thereby reducing the risk. At the same time, the discharge channel and the discharge holes are arranged around the cooling plate, so that the cooling plate can quickly cool the splashes.

[0032] There is a step protruding radially inwards in the positioning groove 14, and the height of the step is the same as the height of the upper surface of the cooling plate 13. Confluence plates 17 are arranged at both ends in the length direction of the limiting strip 2, and confluence channels are arranged in the confluence plates 17; both ends of the cooling plate 13 are connected to the corresponding confluence plates 17, and the cooling channels are communicated with the confluence channels.

[0033] The above are only the preferred embodiments of the present invention, and the present invention is not limited thereto. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A battery system with both high energy density and high power density, characterized in that, It includes a box body (1) which has cylindrical lithium batteries (2) arranged in sequence along the transverse and longitudinal directions. A cylindrical lithium-ion supercapacitor (3) is arranged in the gap between two adjacent rows of the cylindrical lithium batteries (2); all the cylindrical lithium batteries (2) are electrically connected to form a lithium-ion battery system, and all the lithium-ion supercapacitors (3) are electrically connected to form a lithium supercapacitor system; the voltage of the lithium-ion battery system matches the voltage of the lithium supercapacitor system, and a battery management system is connected thereto.

2. The battery system with both high energy density and high power density as described in claim 1, characterized in that, The lithium-ion battery system and the lithium supercapacitor system are arranged in parallel and connected to the battery management system.

3. The battery system with both high energy density and high power density as described in claim 1, wherein, The battery management system includes a lithium-ion battery management system and a lithium supercapacitor battery management system. The lithium-ion battery system is electrically connected to the lithium-ion battery management system, and the lithium supercapacitor system is electrically connected to the lithium supercapacitor battery management system.

4. The battery system with both high energy density and high power density as described in claim 1, characterized in that, The diameter of the cylindrical lithium battery (2) is 46mm, 60mm or 66mm; the diameter of the lithium-ion supercapacitor (3) correspondingly is 19mm, 24mm or 27mm.

5. The battery system with both high energy density and high power density as claimed in claim 1, wherein The box body (1) includes a bottom plate (11). The bottom plate (11) has limiting strips (12) extending along the length direction or the width direction. A plurality of the limiting strips (12) are arranged side by side at equal intervals. A receiving groove is formed between two adjacent limiting strips (12). A cooling plate (13) extending along the length direction is arranged in the receiving groove. A cooling flow channel is arranged in the cooling plate (13). The cylindrical lithium batteries (2) are sequentially arranged on the cooling plate (13) in the receiving groove; the lithium-ion supercapacitors (3) are arranged between the gaps of the cylindrical lithium batteries (2) and are located on the limiting strips (12).

6. The battery system with both high energy density and high power density as claimed in claim 5, wherein On the opposite sides of two adjacent limiting strips (12), there are oppositely arranged and arc-shaped positioning grooves (14). Two mutually opposite positioning grooves (14) are combined into a receiving cavity. A plurality of the receiving cavities are evenly arranged along the length direction of the limiting strip (12); the inner diameter of the receiving cavity matches the diameter of the cylindrical lithium battery (2), and the cylindrical lithium battery (2) is placed in the receiving cavity.

7. The battery system with both high energy density and high power density as described in claim 6, characterized in that On two adjacent limiting strips (12), there are bosses (15) extending towards the middle. The bosses (15) are located between two adjacent receiving cavities; the cooling plate (13) is erected on the bosses (15) and forms a discharge cavity (16) with the bottom of the receiving groove; there is a discharge channel communicating with the discharge cavity (16) between the cooling plate (13) and the positioning groove (14) or on the cooling plate (13), and the discharge channel corresponds to the position of the explosion-proof valve at the bottom of the cylindrical lithium battery (2).

8. The battery system with both high energy density and high power density according to claim 7, characterized in that, The positioning groove (14) has a step protruding radially inwards, and the height of the step is the same as the height of the upper surface of the cooling plate (13).

9. The battery system with both high energy density and high power density as claimed in claim 5, characterized in that Confluence plates (17) are provided at both ends in the length direction of the limiting strip (12), and a confluence flow channel is provided in the confluence plate (17); both ends of the cooling plate (13) are connected to the corresponding confluence plates (17), and the cooling flow channel is communicated with the confluence flow channel.

10. The battery system with both high energy density and high power density as described in claim 5, characterized in that, A heat-conducting material is filled between the cooling plate (13) and the cylindrical lithium battery (2).

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