Introduction and Structure of Lithium ion Battery

Introduction and Structure of Lithium ion Battery

I. Introduction of lithium ion battery

Lithium ion battery refers to the secondary battery in which Li+ embedded compound is positive and anode.

Lithium compounds LiCoO2, LiXNiO2, LiXMnO2, LiFePO4 and ternary composite materials are used in the positive electrode.

Lithium - carbon interlaminar compound -LiXC6 is used in the anode electrode

During the charging process, LI+ inserts and disinserts back and forth between the two electrodes, which is vividly called the "rocking chair battery".

When charging, Li+ falls off from the positive electrode and is embedded into the negative electrode through electrolyte. The negative electrode is in a lithium rich state and the side is opposite when discharging.

Second, lithium ion battery structure

Positive electrode: active substance, conductive agent, solvent, adhesive, matrix;

anode electrode: active substance (graphite, MCMB, CMS), solvent, adhesive, matrix, diaphragm, electrolyte;

Shell hardware: steel case, aluminum case, cover plate, pole lug, insulation sheet, insulation tape;

 

1, lithium ion battery structure - positive electrode

Battery discharge from the external circuit to obtain electrons of the electrode, at this time the electrode reduction reaction, usually high potential electrode, lithium cobalt acid, lithium manganese acid electrode in lithium ion battery;

2, lithium ion battery structure - negative electrode

When the battery discharge from the external circuit to transport electrons electrode, electrode oxidation reaction, usually low potential electrode, graphite electrode in lithium ion batteries;

3, lithium battery structure - diaphragm

Diaphragm - is placed between the poles; A device serving as an isolating electrode; It is used to avoid the short circuit inside the battery caused by direct contact of the active substance on the battery poles, but the diaphragm still needs to be able to let charged ions through; A pathway has been formed;

Diaphragm requirements:

Ionic transmissivity is high

Proper mechanical strength

The insulator itself does not react with the electrolyte and the battery level