Characteristics and classification of lithium batteries

Date:Aug 08, 2019

Lithium battery features

1. It has higher weight-to-energy ratio and volume-to-energy ratio;

2, the voltage is high, the voltage of the single-cell lithium battery is 3.6V, which is equal to the series voltage of 3 nickel-cadmium or nickel-hydrogen rechargeable batteries;

3, self-discharge can be stored for a long time, this is the most outstanding superiority of the battery;

4. No memory effect. Lithium batteries do not have the so-called memory effect of nickel-cadmium batteries, so lithium batteries do not need to be discharged before charging;

5, long life. Under normal working conditions, the number of charge/discharge cycles of the lithium battery is much greater than 500 times;

6, can be quickly charged. The lithium battery can usually be charged with a current of 0.5 to 1 times, so that the charging time is shortened to 1 to 2 hours;

7, can be used in parallel;

8, because the battery does not contain heavy metal elements such as cadmium, lead, mercury, etc., no pollution to the environment, is the most advanced green battery in the modern;

9, high cost. Lithium batteries are more expensive than other rechargeable batteries.

Lithium battery structure

Lithium batteries usually have two appearances: cylindrical and rectangular.

The inside of the battery adopts a spiral wound structure, and is formed by spacing a positive and negative electrode with a very fine and highly permeable polyethylene film insulation material. The positive electrode includes a lithium ion collector composed of lithium and cobalt dioxide and a current collector composed of an aluminum film. The negative electrode is composed of a lithium ion collector composed of a sheet-like carbon material and a current collector composed of a copper film. The battery is filled with an organic electrolyte solution. Safety valves and pTC components are also installed to protect the battery from damage during abnormal conditions and output short circuits.

The voltage of a single-cell lithium battery is 3.6V, and the capacity cannot be infinite. Therefore, single-cell lithium batteries are often serially and parallelly processed to meet the requirements of different occasions.

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