Lithium-ion battery over-temperature protection system and method

Abstract

The invention discloses a system and a method for lithium ion battery over-temperature protection, wherein the system comprises a lithium ion battery set, a temperature detecting circuit, a micro controller unit (MCU) central control unit, a switch module, a discharging circuit, a charging circuit, a power module and an alarm. The lithium ion battery set is electrically connected with the power module, and the temperature detecting circuit is electrically connected with the switch module. The MCU central control unit is electrically connected with the temperature detecting circuit, the power module, the alarm and the switch module. The discharging circuit and the charging circuit are electrically connected with the lithium ion battery set by being electrically connected with the switch module.

Description

technical field [0001] The invention relates to the field of power supplies, in particular to a lithium-ion battery overtemperature protection system and method. Background technique [0002] At present, lithium-ion batteries have become the first choice for power and energy storage due to their advantages such as high working voltage, high energy density, long cycle life, and no environmental pollution. But the explosion of lithium-ion batteries due to overheating is the main obstacle to their current application. In practical applications, lithium-ion batteries need a well-maintained temperature environment to ensure their long-term reliable operation. If the temperature is too high, it will not only accelerate the decline and aging of battery performance, but also cause a series of internal thermal effects of the battery, such as the decomposition of positive and negative electrode materials, oxidation of organic electrolyte, and shedding of SEI film, which will eventual...

AI Technical Summary

Problems solved by technology

However, there are two deficiencies in this patent: (1), the maximum temperature allowed by the battery under the condition of charging and discharging is different

The technical solution proposed by this patent is to carry out over-temperature protection control when the same temperature is reached. In this way, if the critical temperature is set as the maximum temperature allowed under the charging condition, then under the discharging condition, when the battery temperature reaches the critical temperature, the battery will The discharge is cut off, but at this time the battery is still in normal working condition, causing unnecessary actions

(2) The patent uses two chips for the temperature detection circuit and the over-temperature control circuit, which makes the circuit complicated and increases the cost to a certain extent

[0004] In a patent document with the announcement number "CN101373893" and the title "Battery Over-Temperature Protection Circuit" announced by the China Intellectual Property Office on February 25, 2009, another battery over-temperature protection circuit was disclosed. Its principle is the same as that of the above-mentioned patent The principle is similar, the difference is: (1), the patent has separately dealt with the maximum safe temperature in two different cases of battery charge and discharge; It is very troublesome to reset, the reference voltage module of the whole circuit needs to be changed

(2) In terms of circuit design, this patent does not use a smart chip, but uses a reference voltage supply circuit and a comparison module instead

Although this reduces the circuit cost to a certain extent, it makes the circuit more complicated

At the same time, with the increasing demand for practical applications, the lack of a chip also means that the application cannot change the critical temperature of the battery at any time, the applicable battery type is reduced, and the battery temperature curve cannot be drawn, etc.

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