Lithium ion battery protector

Abstract

The invention discloses a lithium ion battery protector which comprises a circuit break protection switch made of shape memory alloy. The circuit break protection switch comprises two contacts at the two sides. At a normal temperature, the contacts at the two sides are contacted; and when at a memory temperature, the contacts at the two sides are separated. The lithium ion battery protector utilizes the memory performance of the shape memory alloy, so that the anti-interference and anti-high-voltage capability and passive over-current capability are improved, and a complex protection system for the lithium ion battery is simplified; and the battery is modularized, so that the defects, such as short service life, poor stability, weak anti-interference capability, weak anti-high-voltage capability and weak anti-over-current capability and the like at present, of an electronic semiconductor (such as MOSFET) are overcome, and the problem of the safety of the lithium ion battery is effectively solved. The physical characteristics of the material of the switch are utilized, so that when temperature signals are utilized to trigger the switch, the cell balancing and over charge inhibition function are taken into consideration, the battery module can be guaranteed to realize predictable random series/parallel connection usage, and the usage threshold of the power lithium battery is reduced.

Description

technical field [0001] The invention relates to a lithium ion battery protector, in particular to a lithium ion battery protector using a shape memory alloy. Background technique [0002] Power lithium-ion batteries are more and more widely used in various equipment, including automobiles, UPS, power storage, and field power. It has the advantages of large capacity and small size, and is the mainstream of the current battery market. However, when a lithium-ion battery encounters abnormal conditions such as short circuit and overcharge, it is easy to cause the battery to heat up violently. If there are no protective measures at this time, vicious accidents such as explosion and combustion will occur. Therefore, lithium-ion batteries must be forced to install overvoltage, overtemperature, and overcurrent protection devices. [0003] One of the main technical difficulties in replacing traditional lead-acid batteries with secondary lithium-ion batteries is the need to install ...

AI Technical Summary

Problems solved by technology

Although switching devices such as disconnect relays and MOSFETs are flexible in application and quick in action, due to the complexity of peripheral control and drive circuits, the overall reliability of the system is low, and semiconductor devices such as MOSFETs and IGBTs have poor anti-interference ability and current shock resistance. Poor problems; while relays have defects such as slow action, large drive current, and bulky devices

In the grouping process of existing lithium-ion battery packs, there are many control points. When power lithium-ion batteries need to be used in series and parallel, the management is very complicated. Often, the cost of a battery pack system and the protection system account for more than half of the total cost.

On the other hand, the current electronic semiconductor switches (such as MOSFET) have defects such as short life, poor stability, weak anti-interference ability, and weak high-voltage resistance ability.

[0005] In electric tools, electric bicycles, small energy storage and other application fields, a certain number of cells must be connected in series and parallel to achieve the voltage and capacity required by the application, but the defects of the above-mentioned relays, MOSFETs, IGBTs and other switching devices greatly limit the Their application in such fields

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