Charge-discharge protective system of lithium battery pack

Abstract

The present invention discloses a charge-discharge protective system of a lithium battery pack including a voltage sampling circuit, a current sampling circuit, a temperature sampling circuit, a load state feedback circuit, a discharge circuit, a charge circuit and a singlechip computer. The voltage sampling circuit is used for sampling voltage of the lithium battery pack, the current sampling circuit is used for sampling current of the lithium battery pack, and the temperature sampling circuit is used for sampling temperature of the lithium battery pack. Output ends of the voltage sampling circuit, the current sampling circuit, the temperature sampling circuit and the load state feedback circuit are electrically connected with the input end of the singlechip computer separately. The output end of the singlechip computer is electrically connected with the charge circuit and the discharge circuit separately. The charge protective system of the lithium battery pack also includes a fuse circuit, and the fuse circuit is connected with the charge circuit in series. The discharge protective system of the lithium battery pack also includes earth leakage protection. Compared to the prior art, the charge-discharge protective system of the lithium battery pack improves the reliability and safety of the protection control of the lithium battery pack, and avoids safety accidents due to invalid overcharge protection and no-load leakage current.

Description

technical field [0001] The invention relates to a charging and discharging system for a lithium battery pack, in particular to a three-stage charging and discharging protection system for a lithium battery pack. Background technique [0002] At present, the charging and discharging protection system of lithium battery packs is customary to use a simple analog comparison circuit to judge the overvoltage and undervoltage of each string of lithium battery packs, the overcharge and overdischarge of charging and discharging current, and the temperature control switch. High temperature and low temperature protection, directly control the Mos tube in the loop (the Mos tube is a metal (metal)-oxide (oxid)-semiconductor (semiconductor) field effect transistor). However, there are no corresponding protection measures for comparison judgment failure, Mos tube failure, and leakage current in the circuit. Once the comparison judgment in the protection system fails, or the Mos tube fails...

AI Technical Summary

Problems solved by technology

However, there are no corresponding protection measures for comparison judgment failure, Mos tube failure, and leakage current in the circuit

Once the comparison judgment in the protection system fails, or the Mos tube fails, or there is leakage in the non-working state, the charging and discharging protection system of the entire battery pack will not be able to protect, which may cause the entire battery pack and even electric vehicles. Components caught fire, and even caused a large fire, threatening people's lives and property

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