EV Battery Self-Heating via Internal Discharge
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electric vehicles face limitations in battery performance and safety at low temperatures, as lithium-ion batteries experience reduced capacity and increased risk of internal short circuits when charged at low temperatures, and existing heating methods are not effectively adapted for mobile applications.
Innovation Solution
A power system for electric vehicles that includes a battery heater connected to the battery group, a battery management device, and an isolation inductor, allowing the battery to heat itself through large current discharge, eliminating the need for external power and enabling efficient heating modes based on temperature and residual charge levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If external power sources or thermal insulation materials are used to heat the battery, then the battery temperature can be maintained, but the device complexity increases and the methods are not suitable for mobile applications
Solution Approach 1:
The battery heats itself by utilizing its own residual electric quantity to generate heat through internal resistance during discharge, eliminating the need for external heating devices or power sources. This self-service approach reduces device complexity while maintaining battery temperature in mobile applications.
2Quantity of substance
If the battery is charged at low temperature, then the battery capacity can be utilized, but lithium ions deposit on the negative electrode causing safety problems and reduced battery life
Solution Approach 1:
The system performs preliminary heating of the battery using its own residual energy before charging operations begin. By raising the battery temperature above the freezing point through internal discharge and heat generation, the system ensures that subsequent charging occurs at safe temperatures, preventing lithium ion deposition and associated safety hazards.
3Temperature
If the battery heater is controlled to heat the battery group, then the battery temperature increases, but the residual electric quantity decreases
Solution Approach 1:
The system converts the harmful effect of battery heat generation during discharge into a beneficial heating function. By controlling the discharge current and utilizing the internal resistance, the battery's own operational characteristics are transformed into a self-heating mechanism, where the discharge process that normally consumes energy also provides the necessary heat.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution allows electric vehicles to operate safely and efficiently at low temperatures by directly heating the battery group, reducing restrictions on use and extending battery life through precise heating control.
Implementation Method 1
a battery heater, connected with the battery group and configured to charge and discharge the battery group to heat the battery group
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A power system of an electric vehicle, an electric vehicle comprising the same and a method for heating a battery group of the electric vehicle are provided. The power system comprises: a battery group (101); a battery heater (102) connected with the battery group (101); a battery management device (103) connected with the battery group (101) and the battery heater (102) respectively, and configured to control the battery heater to heat the battery group in a running heating mode or in a parking heating mode according to a temperature and a residual electric quantity of the battery group when the temperature of the battery group is lower than a first heating threshold and the residual electric quantity of the battery group is larger than a parking electric quantity threshold; a motor controller (106) connected with a motor (105) and an electric distribution box (104) respectively; and an isolation inductor (L2).