A single-cell lithium battery protection chip with precise delay and sleep function

Abstract

The invention relates to a single lithium battery protection chip with accurate delay and dormancy functions. The chip internally comprises a control module and a detection module, wherein the detection module is used for comparing a voltage at the end VDD of a lithium battery with an overcharge detection voltage and an overdischarge detection voltage and comparing a voltage at the end VM with an overcurrent detection voltage, a short-circuit detection voltage and a charge detection voltage to obtain comparison signals; the control module is used for processing the comparison signals, judging the working state of the lithium battery and cutting off a charge or discharge switch to protect the lithium battery according to the actual situation. When the lithium battery just enters an overdischarge state, a difference between the voltage at the end VDD and the voltage at the end VM is detected; when the value of VDD-VM is lower than that of a dormancy detection voltage and an external circuit does not form a short circuit, the control module is used for controlling the chip to enter the dormancy state to reduce the power consumption and prolong the work time; protection measures adopted when the lithium battery enters an abnormal state are kept, and when the state of the lithium battery is restored, the charge or discharge switch is switched on to remove the abnormal state.

Description

technical field [0001] The invention belongs to the field of lithium battery protection, and relates to a lithium battery protection chip, in particular to a single lithium battery protection chip with precise time delay and dormancy functions. Background technique [0002] With the development of society and the continuous consumption of petrochemical energy, people are actively looking for new energy to replace the petrochemical energy that will be exhausted one day. Electric energy is one of the ideal substitutes for fossil energy, so people's demand for electric energy has been increasing in recent years. With the development and popularization of unmanned electronic equipment, portable digital equipment, electric tools, electric vehicles, etc., the power core - the battery is receiving more and more attention. Lithium batteries are favored by manufacturers for their high specific energy, long cycle life, small self-discharge, no memory effect, and environmental protect...

AI Technical Summary

Problems solved by technology

However, due to the complex internal structure of lithium batteries and the complex chemical reactions of charge and discharge, there are still many problems when used as a power source.

First of all, lithium batteries cannot withstand overcharge and overdischarge; secondly, when the number of lithium batteries is connected in series and parallel, there will be problems such as unbalanced battery discharge in the battery pack, and the battery pack must be managed with balanced charge and discharge; at the same time, lithium batteries can only Work within a certain range of current and within a certain temperature range

When the lithium battery works under unsuitable conditions, such as overheating, overcharging, overdischarging, excessive operating current, short circuit of the external circuit, etc., the working efficiency of the lithium battery will be reduced, and the service life of the lithium battery will be shortened. Directly damage the lithium battery

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