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Lithium-ion Battery
A lithium-ion battery, also known as the Li-ion battery, is a type of secondary (rechargeable) battery composed of cells in which lithium ions move from the anode through an electrolyte to the cathode during discharge and back when charging.
There are several specific advantages to lithium-ion batteries. The most important advantages are their high cell voltage, high energy density, and no memory effect.
Lithium-ion batteries are used in many laptop computer batteries, cordless power tools, certain electric cars, electric kick scooters, most e-bikes, portable power banks, and LED flashlights.
Lithium-ion Battery
A lithium-ion battery, also known as the Li-ion battery, is a type of secondary (rechargeable) battery composed of cells in which lithium ions move from the anode through an electrolyte to the cathode during discharge and back when charging.
The cathode is made of a composite material (an intercalated lithium compound) and defines the name of the Li-ion battery cell. The anode is usually made out of porous lithiated graphite. The electrolyte can be liquid, polymer, or solid. The separator is porous to enable the transport of lithium ions and prevents the cell from short-circuiting and thermal runaway.
Chemistry, performance, cost, and safety characteristics vary across types of lithium-ion batteries. Handheld electronics mostly use lithium polymer batteries (with a polymer gel as electrolyte), a lithium cobalt oxide (LiCoO2) cathode material, and a graphite anode, which offer high energy density.
Li-ion batteries, in general, have a high energy density, no memory effect, and low self-discharge. One of the most common types of cells is 18650 battery, which is used in many laptop computer batteries, cordless power tools, certain electric cars, electric kick scooters, most e-bikes, portable power banks, and LED flashlights. The nominal voltage is 3.7 V.
Note that non-rechargeable primary lithium batteries (like lithium button cells CR2032 3V) must be distinguished from secondary lithium-ion or lithium-polymer, which are rechargeable batteries. Primary lithium batteries contain metallic lithium, which lithium-ion batteries do not.
Applications of Lithium-ion Batteries
The most common Li-ion type in small consumer electronics (laptops-cell phones) is lithium-cobalt-oxide (LCO) due to its high specific energy. Tesla Motors uses laptop-sized LCO cells in their EVs combined with a liquid cooling system safety issues, but low specific power and life span prevent this type to be a good choice for EVs.
On the other hand, lithium-iron-phosphate (LiFePO4/LFP) does not experience thermal runaway and has almost no fire hazards since no oxygen is released at high temperatures. LiFePO4 cells have a good life span, low costs per Ah and kW, good power capabilities, and are extremely safe, but the specific energy is low, and the performance is poor at low temperatures.
