Energy storage anti-capacity-exceeding protection system

Abstract

The invention relates to the technical field of battery overcharge prevention, and discloses an energy storage anti-overcapacity protection system which comprises an energy storage battery pack composed of a plurality of lithium battery monomers, and the lithium battery monomers are connected in parallel through a high-voltage mainboard and are subjected to charge and discharge control and battery management through a battery management system. The heat exchange unit is used for absorbing heat energy on the lithium battery monomers in a heat transfer manner, and the heat energy enables the matched thermal expansion unit to act so as to change the lithium battery monomers or change the positions of the contacts conducting with the lithium battery monomers, so that the on-off control of the single lithium battery monomers is realized; therefore, a single battery can be controlled in an integrated battery module. Compared with the traditional working principle of intervention after thermal expansion of the batteries, the online state of each single battery in the battery pack can be independently adjusted by utilizing heat energy.

Description

Technical Field

[0001] The invention relates to the technical field of battery overcharge prevention, in particular to an energy storage over-capacity prevention protection system. Background Art

[0002] The existing Chinese patent publication number (CN104752680A) includes a bag in which a battery cell is encapsulated. The electrode tab extends from the end of the battery cell to allow current to flow through, and is composed of a first and a second electrode tab portion. A circuit breaker is provided in the bag, and the circuit breaker is connected to the first and second electrode tab portions so that the first and second electrode tab portions are separated from each other when the battery cell expands. The existing Chinese patent publication number (CN110299574A) discloses a battery overcharge protection device, including a protection unit and an overcharge detection unit connected to a target battery shell; the protection unit includes a conductor located between two adjacent target battery shells and a movable conductive contact located on the target battery shell that can be in contact with the conductor and electrically connected, and the movable conductive contacts are disposed on two opposite sides of the same target battery shell and the two movable conductive contacts are electrically connected; the overcharge detection unit includes a displacement sensor and a controller electrically connected to the displacement sensor; the displacement sensor is used to detect the displacement of a sliding cold plate attached to the surface of the target battery shell due to the overcharge expansion of the target battery. The battery overcharge protection device of the present invention can improve the stability and safety of the battery through the protection unit when the battery is overcharged, that is, when the entire battery pack or a single battery module swells due to overcharge, the overcharge can be prevented by short circuiting.

[0003] However, the above patent only intervenes after the battery pack undergoes mechanical deformation. Although the power supply is disconnected, the internal structure of the battery pack is likely to be damaged, and the battery pack still contains a large amount of energy, which can easily lead to a short circuit and then irreversible damage, temperature rise, explosion, etc. The minimum impact is that the battery capacity is greatly reduced. In addition, the existing energy storage battery packs and power battery packs are integrated from several small batteries, and there must be power differences during charging. The capacity of each small battery cell is the same when leaving the factory, but due to different charging efficiencies (affected by resistance, current, voltage, and temperature differences of each small battery), some battery cells are already fully charged while others are not. In this case, if charging is not continued and in the long run, the difference in battery energy storage will become larger and larger, which is not conducive to improving capacity utilization. However, if charging is continued, the fully charged battery will heat up and expand. Summary of the invention

[0004] The technical problem to be solved by the present invention is: in order to overcome the above problems, an energy storage overcapacity protection system is provided, which solves the above problems.

[0005] The present invention solves the technical problem by adopting the following technical solutions: The energy storage overcapacity protection system includes an energy storage battery pack composed of a plurality of lithium battery cells, and the lithium battery cells are connected in parallel by a high-voltage mainboard and are controlled for charge and discharge and managed by a battery management system. In addition, it also includes a heat exchange unit for absorbing heat energy from the lithium battery cells by heat transfer, and using this heat energy to activate the matching thermal expansion unit to change the lithium battery cells or change the position of the contacts that are conductive to the lithium battery cells, thereby controlling the on and off of a single lithium battery cell, and thus being able to control a single battery in an integrated battery module.

[0006] In one embodiment, in order to achieve a better control effect, a voltage regulator with a mechanical adjustment lever is also provided, wherein the driving end of the thermal expansion unit or a component rigidly fixedly connected to the driving end of the thermal expansion unit is connected to the adjustment lever of the voltage regulator, so that when the thermal expansion unit is actuated, the voltage regulator will adjust the input voltage to the lithium battery cell and then adjust the charging power of the single lithium battery cell, thereby achieving the technical effect of individual temperature control and uniform charging.

[0007] In one embodiment, the lithium battery cell is fixed by a battery integrated shell, and a thermal imbalance regulator is fixedly provided on the battery integrated shell, a heat absorption row is attached to the side wall of the lithium battery cell for absorbing heat energy of the lithium battery cell during charging through heat transfer, and the heat absorption row is a hollow design with silicone grease inside, the heat absorption row is fixed and connected to a heat conducting pipe, the heat conducting pipe is fixedly connected to the thermal imbalance regulator, the heat conducting pipe and the thermal imbalance regulator are filled with heat conducting oil with a density less than that of silicone grease, and the thermal imbalance regulator expands after absorbing heat so that the piston arm at its end moves to push the lithium battery cell or the electrode that supplies power to the lithium battery cell.

[0008] In one embodiment, the thermal imbalance regulator includes a thermal expansion cylinder fixed on the battery integrated shell and a telescopic cylinder fixed at the lower end of the thermal expansion cylinder. A piston arm is provided in the telescopic cylinder for telescopic movement, and the diameter of the thermal expansion cylinder is at least five times the diameter of the telescopic cylinder, which is conducive to amplifying the expansion thrust.

[0009] In one embodiment, a battery online regulator is also fixedly provided on the battery integrated shell, and two power supply electrodes are provided in the battery online regulator. Battery end clamps are fixedly provided on the upper and lower ends of the lithium battery cell, and a battery electrode electrically connected to the internal cell of the lithium battery cell is provided on the battery end clamp at the upper end. The lithium battery cell has an up and down sliding stroke in the battery integrated shell, and a load-bearing spring is provided at the lower end of the lithium battery cell to lift the lithium battery cell upward so that the battery electrode is connected to the power supply electrode in the battery online regulator. When the heat of the lithium battery cell accumulates so that the material inside the thermal expansion cylinder exceeds the specified thermal expansion amount, the piston arm pushes downward to separate the battery electrode from the power supply electrode, so that the single lithium battery cell will go offline, thereby preventing its temperature from rising rapidly under continuous charging. Compared with the prior art in which the safety device is intervened only when the battery is mechanically deformed, the present application is safer.

[0010] In one embodiment, we can also replace the power supply electrode in the battery online regulator with a voltage regulator, which connects the power supply line introduced by the battery management system to form a power supply path for the lithium battery cell through a soft power supply line, and a mechanical adjustment lever is provided on the voltage regulator to cooperate with a movable piston arm. When the piston arm moves downward, the voltage regulator is pushed to adjust the input voltage and power downward, which can achieve a good power distribution effect with the battery management system, thereby compensating for the defect of insufficient charging caused by different charging speeds between different lithium battery cells.

[0011] In one embodiment, a follow-up adjustment arm is fixedly provided on the upper end of the lithium battery cell, and the follow-up adjustment arm is connected to the mechanical lever on the voltage regulator. When the lithium battery cell is displaced by the piston arm, it will synchronously drive the follow-up adjustment arm to adjust the voltage regulator.

[0012] In one embodiment, an installation gap is provided between the lithium battery cells for heat dissipation, and an air supply row is embedded in the installation gap. The air supply row is a hollow plate-like structure, and an exhaust hole is provided on the end face of the air supply row. The air supply row is supplied with air by an air supply pipe connected to the top of the air supply pipe. An industrial motor supplies air to the air supply pipe, and an electric heater is provided in front of the blowing channel of the industrial motor, so that heat dissipation or heating air can be provided to control the temperature of the lithium battery cells, thereby increasing the charging power of the battery while meeting the safety requirements.

[0013] In one embodiment, a battery integrated outer shell is provided on the outside of the lithium battery cell for mechanical protection, and heat dissipation holes for exhaust are provided at intervals on the battery integrated outer shell.

[0014] The advantages and positive effects of the present invention are: compared with the traditional working principle of intervening after thermal expansion of the battery, the present device uses thermal energy to enable each single battery in the battery pack to adjust the online state individually. When the battery temperature reaches the set safety threshold, the thermal imbalance regulator expands due to the transfer of heat, causing the lithium battery monomer to move downward, which will enable the embodiment of using the battery electrode to control the single lithium battery monomer to go offline, that is, the battery electrode is separated from the contact set in the battery online regulator, so that the battery monomer will not continue to charge and thus avoid overcharging out of control; In addition, when the voltage regulator is used as the embodiment structure, the thermal imbalance regulator expands due to the temperature difference and drives the lithium battery monomer to move downward, so that the follower adjustment arm controls and adjusts the voltage regulator under mechanical action to reduce the charging voltage and power of the lithium battery monomer, which can effectively reduce its temperature rise runaway efficiency, and the device can regulate the power of each battery monomer through the temperature difference in the trickle stage when the battery is nearly full, which is conducive to making the charging capacity of each battery monomer uniform, which can effectively improve the utilization rate of the battery and reduce the probability of overcharging of a single battery, and can improve the overall charging speed of the battery; In addition, the above two embodiments can prevent the mechanical structure of the battery body from being deformed and causing irreversible damage; In addition, an air supply duct and an air supply exhaust are provided for heating or dissipating heat to the lithium battery cells at appropriate times. Heating can be used to quickly increase battery activity and accelerate charging efficiency at the initial stage of charging, and heat dissipation is used to stabilize the battery temperature to avoid exceeding a safe temperature. The air supply exhaust is arranged in the middle of the gap between the lithium battery cells and effectively conducts heat convection exchange with the outer wall of the lithium battery cells in a narrow gap through the action of the battery integrated outer shell. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0016] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 yes Figure 1 Schematic diagram of the internal structure (only one set of heat pipes 21 and heat absorbing row 20 are shown); Figure 3 It is a schematic diagram of the structure of the air supply pipe 12 and the air supply row 14 in the present invention; Figure 4 is a schematic structural diagram of the thermal imbalance regulator 15 in the present invention; Figure 5 It is a schematic diagram of the structure of the lithium battery cell 23 in the present invention; Figure 6Schematic diagram of the structure of the lithium battery cell 23 in the present invention (another embodiment). DETAILED DESCRIPTION

[0017] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention. The embodiments of the present invention will be described in further detail with reference to the accompanying drawings: like Figure 1-6 As shown, the energy storage overcapacity protection system described in the present invention includes an energy storage battery pack composed of a plurality of lithium battery cells 23, and the lithium battery cells 23 are connected in parallel by a high-voltage mainboard and are controlled for charge and discharge and managed by a battery management system 11. In addition, it also includes a heat exchange unit for absorbing heat energy from the lithium battery cells 23 by heat transfer, and using this heat energy to activate the matching thermal expansion unit to change the lithium battery cells 23 or change the position of the contacts conductive to the lithium battery cells 23, thereby controlling the on and off of a single lithium battery cell 23, and thus being able to control a single battery in an integrated battery module.

[0018] In one embodiment, in order to achieve a better control effect, a voltage regulator 27 with a mechanical adjustment lever is also provided, wherein the driving end of the thermal expansion unit or a component rigidly fixedly connected to the driving end of the thermal expansion unit is connected to the adjustment lever of the voltage regulator 27, so that when the thermal expansion unit is actuated, the voltage regulator 27 will adjust the input voltage to the lithium battery cell 23 and then adjust the charging power of the single lithium battery cell 23, thereby achieving the technical effect of individual temperature control and uniform charging.

[0019] In one embodiment, the lithium battery cell 23 is fixed by a battery integrated shell, and a thermal imbalance regulator 15 is fixedly provided on the battery integrated shell, and a heat absorption row 20 is attached to the side wall of the lithium battery cell 23 for absorbing heat energy of the lithium battery cell 23 during charging through heat transfer, and the heat absorption row 20 is a hollow design with silicone grease inside, the heat absorption row 20 is fixed and connected to a heat pipe 21, and the heat pipe 21 is fixedly connected to the thermal imbalance regulator 15, and the heat pipe 21 and the thermal imbalance regulator 15 are filled with heat-conducting oil with a density less than that of silicone grease, and the thermal imbalance regulator 15 expands after absorbing heat so that the piston arm at its end moves to push the lithium battery cell 23 or the electrode that supplies power to the lithium battery cell 23.

[0020] In one embodiment, the thermal imbalance regulator 15 includes a thermal expansion cylinder 16 fixed on the battery integrated shell and a telescopic cylinder 17 fixed at the lower end of the thermal expansion cylinder 16, a piston arm 18 is telescopically provided in the telescopic cylinder 17, and the diameter of the thermal expansion cylinder 16 is at least five times the diameter of the telescopic cylinder 17, which is conducive to amplifying the expansion thrust.

[0021] In one embodiment, a battery online regulator 22 is also fixedly provided on the battery integrated shell, and two power supply electrodes are provided in the battery online regulator 22. Battery end clamps 24 are fixedly provided at the upper and lower ends of the lithium battery cell 23, and a battery electrode 25 electrically connected to the internal cell of the lithium battery cell 23 is provided on the upper end of the battery end clamp 24. The lithium battery cell 23 has an up and down sliding stroke in the battery integrated shell, and a load spring 29 is provided at the lower end of the lithium battery cell 23 for lifting the lithium battery cell 23 upward so that the battery electrode 25 is connected to the power supply electrode in the battery online regulator 22. When the heat of the lithium battery cell 23 accumulates so that the material inside the thermal expansion cylinder 16 exceeds the specified thermal expansion amount, the piston arm 18 pushes downward to separate the battery electrode 25 from the power supply electrode, so that the single lithium battery cell 23 will be offline, thereby preventing its temperature from rising rapidly under continuous charging. Compared with the prior art in which the safety device is intervened only when the battery is mechanically deformed, the present application is safer.

[0022] In one embodiment, we can also replace the power supply electrode in the battery online regulator 22 with a voltage regulator 27. The voltage regulator 27 connects the power supply line introduced by the battery management system 11 to form a power supply path for the lithium battery cell 23 through a soft power supply line 28. A mechanically adjustable lever is provided on the voltage regulator 27 to cooperate with the movable piston arm 18. When the piston arm 18 moves downward, the voltage regulator 27 is pushed to adjust the input voltage and power downward, which can achieve a good power distribution effect with the battery management system 11, thereby compensating for the defect of insufficient charging caused by different charging speeds between different lithium battery cells 23.

[0023] In one embodiment, a follow-up adjustment arm 26 is fixedly provided on the upper end of the lithium battery cell 23, and the follow-up adjustment arm 26 is connected to the mechanical lever on the voltage regulator 27. When the lithium battery cell 23 is displaced by the piston arm 18, it will synchronously drive the follow-up adjustment arm 26 to adjust the voltage regulator 27.

[0024] In one embodiment, an installation gap is provided between the lithium battery cells 23 for heat dissipation, and an air supply row 14 is embedded in the installation gap. The air supply row 14 is a hollow plate-like structure, and an end face of the air supply row 14 is provided with exhaust holes. The air supply row 14 is supplied with air by an air supply pipe 12 connected to the top thereof. An industrial motor supplies air to the air supply pipe 12, and an electric heater is provided in front of the blowing channel of the industrial motor, so that heat dissipation or heating wind can be provided to control the temperature of the lithium battery cells 23, thereby increasing the charging power of the battery while meeting the safety requirements.

[0025] In one embodiment, a battery integrated outer shell 10 is provided outside the lithium battery cell 23 for mechanical protection, and heat dissipation holes 13 for exhaust are provided at intervals on the battery integrated outer shell 10 .

[0026] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive, and therefore the present invention is not limited to the embodiments described in the specific implementation manners. Any other implementation manners derived by those skilled in the art based on the technical solutions of the present invention also fall within the scope of protection of the present invention.

Claims

1. Energy storage overcapacity protection system, characterized by: The invention comprises an energy storage battery pack composed of a plurality of lithium battery cells (23), wherein the lithium battery cells (23) are connected in parallel by a high-voltage main board and are controlled for charge and discharge and managed by a battery management system (11). In addition, the invention comprises a heat exchange unit for absorbing heat energy from the lithium battery cells (23) by heat transfer, and using the heat energy to activate a matching heat expansion unit to change the lithium battery cells (23), thereby controlling the on and off of a single lithium battery cell (23), and thus being able to control a single battery in an integrated battery module.

2. The energy storage overcapacity protection system according to claim 1 is characterized in that: In order to achieve a better control effect, a voltage regulator (27) having a mechanical adjustment lever is also provided, wherein the driving end of the thermal expansion unit or a component rigidly fixedly connected to the driving end of the thermal expansion unit is connected to the adjustment lever of the voltage regulator (27), so that when the thermal expansion unit is activated, the voltage regulator (27) will adjust the input voltage to the lithium battery cell (23) and thus adjust the charging power of the single lithium battery cell (23), thereby achieving the technical effect of individual temperature control and uniform charging.

3. The energy storage overcapacity protection system according to claim 2 is characterized in that: The lithium battery cell (23) is fixed by a battery integrated shell, and a thermal imbalance regulator (15) is fixedly arranged on the battery integrated shell. A heat absorption row (20) is attached to the side wall of the lithium battery cell (23) for absorbing heat energy during the charging process of the lithium battery cell (23) through heat transfer. The heat absorption row (20) is hollow and has silicone grease inside. The heat absorption row (20) is fixed and connected to a heat conducting pipe (21). The heat conducting pipe (21) is fixed and connected to the thermal imbalance regulator (15). The heat conducting pipe (21) and the thermal imbalance regulator (15) are both filled with heat conducting oil having a density less than that of silicone grease. After absorbing heat, the thermal imbalance regulator (15) expands so that a piston arm at its end moves to push the lithium battery cell (23) or an electrode for supplying power to the lithium battery cell (23).

4. The energy storage overcapacity protection system according to claim 3 is characterized in that: The thermal imbalance regulator (15) comprises a thermal expansion cylinder (16) fixed on a battery integrated shell and a telescopic cylinder (17) fixed at the lower end of the thermal expansion cylinder (16); a piston arm (18) is telescopically provided in the telescopic cylinder (17); and the diameter of the thermal expansion cylinder (16) is at least five times the diameter of the telescopic cylinder (17).

5. The energy storage overcapacity protection system according to claim 4 is characterized in that: A battery online regulator (22) is also fixedly provided on the battery integrated shell, and two power supply electrodes are provided in the battery online regulator (22). Battery end hoops (24) are fixedly provided at the upper and lower ends of the lithium battery monomer (23), and a battery electrode (25) electrically connected to the internal cell of the lithium battery monomer (23) is provided on the upper end of the battery end hoop (24). The lithium battery monomer (23) has an up and down sliding stroke in the battery integrated shell, and a load spring (29) is provided at the lower end of the lithium battery monomer (23) for moving the lithium battery monomer (23) is pushed upward to connect the battery electrode (25) with the power supply electrode in the battery online regulator (22). When the heat of the lithium battery cell (23) is accumulated so that the material inside the thermal expansion cylinder (16) exceeds the specified thermal expansion amount, the piston arm (18) pushes downward to separate the battery electrode (25) from the power supply electrode. In this way, the single lithium battery cell (23) will be offline, thereby preventing its temperature from rising rapidly under continuous charging. Compared with the prior art that intervenes with the safety device only when the battery is mechanically deformed, the present application is safer.

6. The energy storage overcapacity protection system according to claim 4 is characterized in that: A voltage regulator (27) is provided in the battery online regulator (22). The voltage regulator (27) connects the power supply line introduced by the battery management system (11) to form a power supply path for the lithium battery cells (23) through a soft power supply line (28). A mechanically adjustable lever is provided on the voltage regulator (27) for cooperating with a movable piston arm (18). When the piston arm (18) moves downward, the voltage regulator (27) is driven to adjust the input voltage and power downward, thereby achieving a good power distribution effect with the battery management system (11), thereby compensating for the defect of insufficient charging caused by different charging speeds between different lithium battery cells (23).

7. The energy storage overcapacity protection system according to claim 6 is characterized in that: A follow-up adjustment arm (26) is fixedly provided at the upper end of the lithium battery cell (23), and the follow-up adjustment arm (26) is connected to a mechanical lever on the voltage regulator (27). When the lithium battery cell (23) is pushed and displaced by the piston arm (18), it will synchronously drive the follow-up adjustment arm (26) to adjust the voltage regulator (27).

8. The energy storage overcapacity protection system according to any one of claims 1 to 7, characterized in that: An installation gap is provided between the lithium battery cells (23) for heat dissipation, and an air supply row (14) is embedded in the installation gap. The air supply row (14) is a hollow plate-like structure. An end face of the air supply row (14) is provided with an exhaust hole. The air supply row (14) is supplied with air by an air supply pipe (12) connected to the top of the air supply row. An industrial motor supplies air to the air supply pipe (12). An electric heater is provided in front of the air blowing channel of the industrial motor, so that heat dissipation or heating air can be provided to control the temperature of the lithium battery cells (23), thereby increasing the charging power of the battery while meeting the safety requirement.

9. The energy storage overcapacity protection system according to claim 8 is characterized in that: A battery integrated outer shell (10) is provided outside the lithium battery cell (23) for mechanical protection, and heat dissipation holes (13) for exhausting air are provided at intervals on the battery integrated outer shell (10).

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