Low-temperature combined inner and outer heating device and method for lithium ion battery

Abstract

The invention relates to a low-temperature combined inner and outer heating device and method for a lithium ion battery. The device comprises an outer heating module and an inner heating module whichare connected in parallel between a positive electrode of the lithium ion battery and the negative electrode of the lithium ion battery; the outer heating module comprises a first switch, an IGBT module and an outer heating plate which are serially connected in sequence, a PWM control signal is introduced into the IGBT module, and the PWM control signal is received for controlling; the inner heating module comprises a second switch and an alternating current power supply which are serially connected; the state of the outer heating process and the state of the inner heating process are controlled respectively through the respective turning-on and turning-off of the first switch and the second switch; the inner heating module uses the alternating current power supply to generate alternatingcurrent with specific frequency, and then the proportion of the turning-on time of the IGBT module to the turning-off time of the IGBT module is controlled in combination with the change of the duty ratio of the PWM control signal, and then the distribution proportion of the heating power of the outer heating process to the heating power of the inner heating process is controlled, so as to reach low-temperature combined inner and outer heating for the lithium ion battery. The device is simple in structure and good in heating effect, and the distribution proportion of heating power further canbe adjusted to realize optimal heating.

Description

technical field [0001] The invention relates to the technical field of battery heating, in particular to a low-temperature internal and external combined heating device and method for a lithium-ion battery. Background technique [0002] In recent years, due to the depletion of global oil resources and the deterioration of the environment, the use and research of new energy has become the focus of future development in various countries. The development of new energy vehicles is the main technical means generally recognized by countries in the world to solve the problems of energy saving and environmental protection of vehicles, and power batteries (that is, lithium-ion battery) is the core component of the development of new energy vehicles. Studies have shown that when the temperature of the lithium-ion battery is too low, the released power and capacity will be significantly reduced, and the lithium ion deposition caused by high-rate charging and overcharging will lead to ...

AI Technical Summary

Problems solved by technology

[0006] The present invention aims at low-temperature heating of lithium-ion batteries in the prior art, usually only using a separate external heating method, which is prone to large energy dissipation, low thermal efficiency, large energy loss, large heating temperature gradient and poor heating effect, or only using a separate internal heating method is safe Due to the defects of extremely low resistance, high current charging at low temperature is easy to damage lithium-ion batteries or cause internal short circuits, a low-temperature internal and external combined heating device for lithium-ion batteries is provided, which effectively utilizes the parallel connection between the positive and negative electrodes of lithium-ion batteries The external heating module and the internal heating module realize the combination of internal and external heating to achieve the optimal heating effect on the lithium-ion battery. The structure is simple and the control is convenient, which greatly improves the heating efficiency and enhances the heating effect. It has strong applicability

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