CN218505681U - Battery thermal management system of electric excavator - Google Patents

Abstract

The utility model discloses a battery thermal management system for an electric excavator, which belongs to the technical field of battery management and comprises a battery pack waterway assembly, which includes an external pipeline and a single battery pack connected to the external pipeline. One end of the connection pipe is connected to the water pump, the water pump is connected to the water inlet of the four-way water valve, and the water outlet of the four-way water valve and the other end of the external pipe are connected in parallel to a hot water circulation circuit, a low-temperature refrigeration water circulation circuit and a high-temperature refrigeration water circulation circuit. Under the condition of constant pump flow and head, three different thermal management operation modes are adopted, and the maximum coolant flow can be achieved through the four-way water valve. Each circuit is suitable for temperature adjustment under different conditions, improving the cooling or heating effect of the battery , so that the battery temperature is controlled within a reasonable range to ensure that the battery pack of the electric excavator works within a reasonable temperature range.

Description

A battery thermal management system for an electric excavator

technical field

The utility model belongs to the technical field of battery management, and relates to a battery heat management system for an electric excavator.

Background technique

Electric excavators have the characteristics of zero emissions, low noise, and low maintenance costs. Under the background of rising fuel prices and energy conservation and environmental protection, new energy electric excavators may become the main driving force in the future. When the high-power battery pack on the electric excavator is charged and discharged with a high current, it may cause a violent chemical reaction inside the battery, generate a lot of heat, and make it difficult to dissipate heat in some areas, exacerbating the temperature inconsistency between the cells, which will reduce the battery charge. The discharge efficiency will affect the power of the battery, and in severe cases, it will lead to thermal runaway and cause safety hazards. At low temperatures, the internal resistance of lithium-ion batteries will increase and the capacity will decrease. In extreme cases, the electrolyte will freeze and the battery will not be able to discharge, resulting in attenuation of power output performance and reduction in cruising range. Therefore, the battery temperature needs to be controlled within a reasonable range, and a reasonable battery thermal management system design is of great significance. The electric excavator has a large battery capacity and requires a large number of standard battery packs. Under the condition of a certain water pump flow and lift, and under different thermal management operating modes, how to increase the coolant flow and thus improve the cooling or heating effect of the battery is of great significance.

Utility model content

The technical problem to be solved by the utility model is to provide a battery thermal management system for an electric excavator in view of the deficiencies in the prior art above. The utility model provides the following technical solutions: a battery thermal management system for an electric excavator, including a battery pack Waterway assembly, the battery pack waterway assembly includes an external pipeline and a single battery pack connected to the external pipeline,

One end of the external pipeline is connected to a water pump, the water pump is connected to the water inlet of the four-way water valve, and the water outlet of the four-way water valve is connected in parallel with the other end of the external pipeline. loop and a high-temperature cooling water circulation loop, the heating water circulation loop includes a PTC heater, the low-temperature cooling water circulation loop includes a radiator, a cooling fan is provided on one side of the radiator, and the high-temperature cooling water circulation loop includes a battery cooler , the battery cooler is externally connected to a cooling circuit for heat exchange, and the cooling circuit includes a battery cooler, a compressor, a condenser and an expansion valve connected in sequence to form a circuit, and a condensation fan is arranged on one side of the condenser; the battery There is cooling liquid in the package waterway assembly, hot water circulation circuit, low-temperature refrigeration water circulation circuit and high-temperature refrigeration water circulation circuit, and refrigerant in the cooling circuit;

The single battery pack is provided with a cell temperature sensor, and the external pipelines at both ends of the single battery pack are provided with a water temperature sensor, and both the cell temperature sensor and the water temperature sensor are connected to the battery management system BMS,

The water pump, four-way water valve, PTC heater, cooling fan, compressor and condensing fan are all connected to the independent heat management unit, and the independent heat management unit is connected to the battery management system BMS through the CAN bus.

Preferably, the liquid cold plates of the single battery packs are arranged in series and in parallel.

Preferably, the battery management system BMS is connected to an ambient temperature sensor, and the ambient temperature sensor is used to detect the temperature of the external environment of the single battery pack.

Preferably, the water pump is externally connected to an expansion tank.

Preferably, the four-way water valve is a four-way electromagnetic water valve.

Preferably, the cooling liquid is 50% ethylene glycol aqueous solution.

Beneficial effects: When the water pump flow rate and head are fixed, three different thermal management operation modes are adopted, and the maximum coolant flow rate can be achieved through the four-way water valve. Each circuit is suitable for temperature adjustment under different conditions, improving battery cooling Or heating effect, so that the battery temperature is controlled within a reasonable range, ensuring that the battery pack of the electric excavator works within a reasonable temperature range.

Description of drawings

Figure 1 is a schematic diagram of the thermal management structure of the battery of the present invention;

Figure 2 is a control system diagram of the battery management system BMS and the independent thermal management unit;

Figure 3 is a schematic diagram of the structure of the battery pack waterway assembly;

Explanation of symbols in the figure: 1: battery pack waterway assembly; 2: external pipeline; 3: single battery pack; 4: water pump; 5: four-way water valve; 6: hot water circulation circuit; 601: PTC heater ;7: Low-temperature cooling water circulation loop; 701: Radiator; 702: Cooling fan; 8: High-temperature cooling water circulation loop; 801: Battery cooler; 9: Cooling loop; 901: Compressor; 902: Condenser; 903: Expansion valve ;904: condenser fan; 10: cell temperature sensor; 11: water temperature sensor; 12: battery management system BMS; 13: independent thermal management unit; 14: CAN bus; 15: ambient temperature sensor; 16: ambient temperature sensor.

Detailed ways

The utility model will be described in further detail below in conjunction with the accompanying drawings and specific preferred embodiments.

In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "left side", "right side", "upper part" and "lower part" are based on the orientation or positional relationship shown in the accompanying drawings, only It is for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and "first", "second" and the like do not mean zero The importance of the components should not be construed as a limitation of the present invention. The specific dimensions used in this embodiment are only for illustrating the technical solution, and do not limit the protection scope of the present utility model.

Example 1:

Referring to Figures 1-3, the utility model provides a technical solution, a battery thermal management system for an electric excavator, including a battery pack waterway assembly 1, and the battery pack waterway assembly 1 includes an external pipeline 2 and an external pipeline 2 The connected single battery pack 3, one end of the external pipeline 2 is connected to the water pump 4, the water pump 4 is connected to the water inlet of the four-way water valve 5, and the water outlet of the four-way water valve 5 is connected in parallel with the other end of the external pipeline 2. Hot water circulation circuit 6, low-temperature refrigeration water circulation circuit 7 and high-temperature refrigeration water circulation circuit 8, heating water circulation circuit 6 includes a PTC heater 601, low-temperature refrigeration water circulation circuit 7 includes a radiator 701, and a cooling fan 702 is provided on one side of the radiator 701 The high-temperature cooling water circulation circuit 8 includes a battery cooler 801, and the battery cooler 801 is externally connected to a cooling circuit 9 for heat exchange. The cooling circuit 9 includes a battery cooler 801, a compressor 901, a condenser 902, and an expansion valve 903 that are sequentially connected to form a circuit. A condenser fan 904 is provided on one side of the condenser 902; the battery pack waterway assembly 1, the hot water circulation loop 6, the low-temperature cooling water circulation loop 7 and the high-temperature cooling water circulation loop 8 all have coolant, and the cooling loop 9 has refrigerant; The single battery pack 3 is provided with a cell temperature sensor 10, and the external pipeline 2 at both ends of the single battery pack 3 is provided with a water temperature sensor 11, the cell temperature sensor 10 and the water temperature sensor 11 are both connected to the battery management system BMS12, and the water pump 4. The four-way water valve 5, PTC heater 601, cooling fan 702, compressor 901 and condensing fan 904 are all connected to the independent thermal management unit 13, which is connected to the battery management system BMS12 through the CAN bus 14 .

When in use, the coolant flows in the circuit, and flows through the liquid cooling plate of the single battery pack 3 from the loop to cool down or heat the single battery pack 3, and the battery management system BMS12 receives the temperature data monitored by the sensor, and then According to the temperature data, the independent thermal management unit 13 is controlled to adjust the operation of different modes, and the operation of different components is controlled to keep the single battery pack 3 within a reasonable temperature range.

Furthermore, the liquid cold plate 3 of the single battery pack is arranged in a combination of series and parallel to realize a reasonable match between the flow demand of the liquid cold plate of the single battery pack and the performance of the water pump.

Further, the battery management system BMS12 is connected with an ambient temperature sensor 15 , and the ambient temperature sensor 15 is used to detect the temperature of the external environment of the single battery pack 3 .

Furthermore, the water pump 2 is externally connected to the expansion tank 16, which plays the role of constant pressure and water replenishment for the system.

Further, the four-way water valve 5 is a four-way electromagnetic water valve.

Further, the cooling liquid is 50% ethylene glycol aqueous solution.

Example 2:

On the basis of Embodiment 1, with reference to Figures 1-3, when the cell temperature sensor 10 detects that the average temperature of the cells in the single battery pack 3 is lower than the set value, the water temperature sensor 11 detects that the external pipeline 2 has entered When the water temperature of the single battery pack 3 is lower than the set value, the independent thermal management unit 13 receives the command of the battery management system BMS12 to enter the heating mode, controls the water pump 4 and the four-way water valve 5 to open, and the heating water circulation circuit 6 is connected. The cooling liquid circulates along the circuit composed of the battery pack waterway assembly 1, the water pump 4, the four-way water valve 5, and the PTC heater 601. The cooling liquid flows through the PTC heater 601 for heating, and then flows into the liquid cold plate through the external pipe 2 The single battery pack 3 is heated, and the parallel arrangement method is adopted to reduce the total flow resistance of the waterway system. When the pump flow rate and lift are constant, the total flow rate of the waterway system is increased, and the liquid cold plate of the single battery pack 3 is improved. The coolant flow rate improves the heating capacity of the thermal management system.

Further, the set value of the average temperature of the battery cell is 5 degrees, and the set value of the temperature of the water entering the single battery pack 3 from the external pipeline 2 is 45 degrees.

Example 3:

On the basis of Embodiment 1, with reference to Figures 1-3, when the ambient temperature sensor 15 detects that the temperature of the external environment is lower than the set value, the cell temperature sensor 10 detects that the average temperature of the cells of the single battery pack 3 is high At the set value, when the water temperature sensor 11 detects that the temperature of the water entering the single battery pack 3 from the external pipeline 2 is higher than the set value, the independent thermal management unit 13 receives an instruction from the battery management system BMS12 to enter the low-temperature cooling mode, and controls the water pump 4 The four-way water valve 5 is opened, the low-temperature cooling water circulation circuit 7 is connected, the cooling liquid circulates along the circuit composed of the battery pack waterway assembly 1, the water pump 4, the four-way water valve 5, and the radiator 701, the cooling fan 702 is turned on, and the radiator 701 and cooling fan 702 dissipate the heat of the coolant, thereby cooling the coolant, and then flow into the liquid cold plate through the external pipeline 2 to cool the single battery pack 3. The parallel arrangement reduces the total flow of the water system Resistance, in the case of a certain water pump flow and head, the total flow of the waterway system is increased, the coolant flow of the single battery pack 3 liquid cold plate is increased, and the cooling capacity of the thermal management system is improved.

Further, the setting value of the ambient temperature is 5 degrees, the setting value of the average temperature of the battery cell is 28 degrees, and the setting value of the water temperature of the external pipeline 2 entering the single battery pack 3 is 15 degrees.

Example 4:

On the basis of Embodiment 1, with reference to Figures 1-3, when the ambient temperature sensor 15 detects that the temperature of the external environment is higher than the set value, the cell temperature sensor 10 detects that the average temperature of the cells of the single battery pack 3 is high. At the set value, when the water temperature sensor 11 detects that the temperature of the water entering the single battery pack 3 from the external pipeline 2 is higher than the set value, the independent thermal management unit 13 receives an instruction from the battery management system BMS12 to enter the low-temperature cooling mode, and controls the water pump 4 And the four-way water valve 5 is opened, the high-temperature cooling water circulation circuit 8 is connected, the cooling liquid circulates along the circuit composed of the battery pack waterway assembly 1, the water pump 4, the four-way water valve 5, and the battery cooler 801, and the independent thermal management unit 13 After receiving the command from the battery management system BMS12 to enter the high-temperature cooling mode, the compressor 901 and the condensing fan 904 are turned on, the high-temperature coolant flows through the battery cooler 801, and the heat is taken away by the refrigerant in the cooling circuit 9, and the refrigerant is compressed along the cooler 801, The circuit composed of machine 901, condenser 902 and expansion valve 903 circulates, and the flow direction of the refrigerant is opposite to that of the cooling liquid. The refrigerant dissipates heat in the cooling circuit 9 through the refrigeration cycle and the condenser 902; and then through the external pipeline 2 flows into the liquid cold plate to cool down the single battery pack 3, adopts the parallel setting method, reduces the total flow resistance of the waterway system, and increases the total flow rate of the waterway system and the single battery when the flow rate and head of the water pump are constant. The coolant flow of the 3-pack liquid cold plate improves the cooling capacity of the thermal management system.

Further, the setting value of the ambient temperature is 5 degrees, the setting value of the average temperature of the battery cell is 28 degrees, and the setting value of the water temperature of the external pipeline 2 entering the single battery pack 3 is 15 degrees.

Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions of the present utility model will be obvious to those skilled in the art after reading the above content. Within the scope of the technical concept of the utility model, various equivalent transformations can be performed on the technical solution of the utility model, and these equivalent transformations all belong to the protection scope of the utility model.

Claims (6)

1. A battery thermal management system for an electric excavator, characterized in that it includes a battery pack waterway assembly (1), and the battery pack waterway assembly (1) includes an external pipeline (2) and an external pipeline (2) ) connected to the single battery pack (3), one end of the external pipeline (2) is connected to the water pump (4), the water pump (4) is connected to the water inlet of the four-way water valve (5), and the four-way water Between the water outlet of the valve (5) and the other end of the external pipeline (2), a heating water circulation circuit (6), a low-temperature refrigeration water circulation circuit (7) and a high-temperature refrigeration water circulation circuit (8) are arranged in parallel. The circulation loop (6) includes a PTC heater (601), the low-temperature refrigeration water circulation loop (7) includes a radiator (701), and a cooling fan (702) is arranged on one side of the radiator (701), and the high-temperature refrigeration The water circulation loop (8) includes a battery cooler (801), the battery cooler (801) is externally connected to a cooling loop (9) for heat exchange, and the cooling loop (9) includes battery coolers (801) connected in sequence to form a loop , a compressor (901), a condenser (902) and an expansion valve (903), the condenser (902) is provided with a cooling fan (904) on one side; the battery pack waterway assembly (1), hot water There is coolant in the circulation circuit (6), the low-temperature refrigeration water circulation circuit (7) and the high-temperature refrigeration water circulation circuit (8), and there is refrigerant in the cooling circuit (9); The single battery pack (3) is provided with a cell temperature sensor (10), and the external pipelines (2) at both ends of the single battery pack (3) are provided with a water temperature sensor (11). Both the temperature sensor (10) and the water temperature sensor (11) are connected with the battery management system BMS (12), The water pump (4), four-way water valve (5), PTC heater (601), cooling fan (702), compressor (901) and condensing fan (904) are all connected to the independent thermal management unit (13) , the independent thermal management unit (13) is connected to the battery management system BMS (12) through the CAN bus (14). 2. A battery thermal management system for an electric excavator according to claim 1, characterized in that: the single battery packs (3) are arranged in series and in parallel. 3. A battery thermal management system for an electric excavator according to claim 1, characterized in that: the battery management system BMS (12) is connected to an ambient temperature sensor (15), and the ambient temperature sensor (15) uses It is used to detect the temperature of the external environment of the single battery pack (3). 4. The electric excavator battery thermal management system according to claim 1, characterized in that: the water pump (4) is externally connected to an expansion tank (16). 5. A battery thermal management system for an electric excavator according to claim 1, characterized in that: the four-way water valve (5) is a four-way electromagnetic water valve. 6. A battery thermal management system for an electric excavator according to claim 1, wherein the cooling liquid is 50% ethylene glycol aqueous solution.

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