A lithium battery charge and discharge test system

Abstract

The present invention discloses a lithium battery charge-discharge test system. The system comprises a control unit, a battery monitoring and protection device, an alternating current and direct current conversion module, a direct current electronic load and a lithium battery. The control unit is connected with the battery monitoring and protection device, the alternating current and direct current conversion module and the direct current electronic load. The lithium battery is connected with the battery monitoring and protection device, the alternating current and direct current conversion module and the direct current electronic load. The battery monitoring and protection device performs start and stop control of a direct current power supply and the direct current electronic load. The alternating current and direct current conversion module is configured to charge the lithium battery, and the lithium battery discharges the direct current electronic load. After the alternating current and direct current conversion module converts the alternating current to the direct current, a microprocessor collects voltage and current signals through an A / D conversion circuit and generates required PWM control signals to drive a power switch tube to output direct voltage and perform charging test for the lithium battery.

Description

technical field [0001] The invention belongs to the technical field of rechargeable batteries, and in particular relates to a lithium battery charge and discharge test system. Background technique [0002] Most of the existing lithium battery testing equipment is aimed at single cells, and the testing of finished lithium battery packs basically uses a test system with charge and discharge functions. The testing method is to set up a group of lithium battery packs Charge and discharge at a constant current and record the curve diagram of the process. Through the test of the equipment of the test system, it is mainly to determine whether the lithium battery pack under test can be charged and discharged normally and how much the pack capacity is. The main defects of this test system are: it is impossible to monitor the real-time voltage of the single cell in the lithium battery pack, and if the consistency of the single cell is not high, it may even cause damage to the cell due...

AI Technical Summary

Problems solved by technology

The main defects of this test system are: it is impossible to monitor the real-time voltage of the single cell in the lithium battery pack, and if the consistency of the single cell is not high, it may even cause damage to the cell due to overcharging or over-discharging; The system status in the lithium battery pack is detected. Even if the protection system is not installed in the lithium battery pack, it will still be charged and discharged according to the settings of the test system; the lithium battery pack to be tested has clear voltage and current limits. The system can only perform discharge tests on lithium battery packs below 100V and the voltage cannot be too low. The maximum discharge current can only be less than 50A, and the power during charging will be even smaller.

The test process of charging and discharging is in constant current or constant voltage mode, that is, it can only test the discharge state of the tested lithium battery pack under resistive load or slight fluctuation conditions, while most of the actual application load of the lithium battery pack is inductive. The fluctuation range of the load and discharge current is extremely large, generally tens of times or even higher, that is, the actual working conditions cannot be simulated more realistically.

Since the load of the lithium battery pack is mostly inductive load and the control mode is pulse width modulation, the test system cannot test the anti-interference ability of the lithium battery pack

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