Power battery heating method and system for improving low-temperature cruising range of electric vehicles

Abstract

The invention discloses a power battery method and a power battery heating system for prolonging the low-temperature cruising distance of an electrical vehicle. The recovered braking electrical energy can be distributed according to the heating and charging requirements of a lithium ion battery pack, so that an energy storage lithium ion battery device can be effectively protected and the recovered braking energy can be effectively utilized. An energy control unit is used for judging whether the lithium ion battery pack is charged or heated through the recovered braking electrical energy by monitoring the temperature of the lithium ion battery pack and the state of charge (SOC). The system comprises an energy converter, an inverter, the energy control unit and the lithium ion battery pack, wherein a heater connected to the inverter and the energy control unit is arranged in the lithium ion battery pack. Meanwhile, the invention further provides a method capable of efficiently recovering the braking energy to improve the low-temperature performance of the lithium ion battery pack and prolong the low-temperature cruising distance of the electrical vehicle.

Description

technical field [0001] The invention belongs to the field of energy recovery of electric vehicles, in particular to a control method that can directly apply electric energy recovered from braking energy to battery system heating. Background technique [0002] With its excellent cycle characteristics, high specific energy density, and specific power density, lithium-ion power batteries have become the most researched power sources for electric vehicles. However, the poor low-temperature capacity characteristics of lithium-ion battery packs after grouping are also one of the obstacles to the development of electric vehicles. To solve this problem, various OEMs and battery factories have done a lot of work, including designing power battery preheating and heating systems, improving battery materials, and making insulation and heating devices for battery systems, but the results are not ideal. During the braking process of electric vehicles, a lot of energy is not used. The exi...

AI Technical Summary

Problems solved by technology

However, the poor low-temperature capacity characteristics of lithium-ion battery packs after grouping is also one of the obstacles to the development of electric vehicles.

To solve this problem, various OEMs and battery factories have done a lot of work, including designing power battery preheating and heating systems, improving battery materials, and making insulation and heating devices for battery systems, but the results are not ideal.

During the braking process of electric vehicles, a lot of energy is not used. The existing braking energy recovery system has a low energy recovery rate due to the long path of energy conversion.

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