Lithium ion battery, Advantages and disadvantages

Lithium ion battery: Advantages and disadvantages

Lithium ion battery or Li-ion battery is a type of rechargeable battery in which lithium ions move from the anode to cathode during discharge, and from cathode to anode when charging.

Different classes of li-ion batteries use varying cathodes made of other lithium molecules. The anodes are generally made of carbon. Like any other batteries, chemical reactions between the anode, cathode, and electrolyte produce electric current. The materials used for the anodes and cathodes determine the performance, capacity, cost, and safety of a particular class of li-ion battery.

For example, li-ion batteries based on a cathode made of lithium cobalt oxide provide higher capacity but are more reactive due to poorer thermal capacities. Lithium iron phosphate is another class of lithium ion battery, which on the other hand, have four to five times longer cycle lifetimes, eight to 10 times higher power density, and wider operating temperature range than standard li-ion batteries.

Despite the existence of different classes of li-ion batteries, they remain popular in portable electronics or consumer electronic devices such as laptops and smartphones. This battery is also becoming popular for military, aerospace, and electric automobile applications.

In addition, despite the different characteristics of li-ion batteries due to differences in material composition, most share common or general characteristics. Below are the general advantages and disadvantages of lithium ion battery over other rechargeable batteries:

General advantages of lithium ion battery

1. Smaller and lighter: Li-ion battery is lighter than other rechargeable batteries in consideration of battery capacity. This makes it more practical in portable consumer electronic devices in which physical specifications such as weight and form factor are considered important selling points.

2. High energy density: Li-ion battery has higher energy density than other rechargeable batteries. This means having high power capacity without being too bulky. This is suitable for use in power-hungry devices such as laptops and smartphones. Advancements in technology open potential for higher capacities.

3. Low self-discharge: Li-ion battery also has a low self-discharge rate of about 1.5 percent per month. This means that the battery has a longer shelf life when not in used because it discharges slowly than other rechargeable batteries. Take note that nickel-metal hydride battery has a self-discharge of 20 percent per month.

4. Zero to low memory effect: Li-ion battery has zero to minimal memory effect. Take note than memory effect is a phenomenon observed in rechargeable batteries in which they lose their maximum energy capacity when repeated recharged after being only partially discharged. This memory effect is common in nickel-metal hydride rechargeable batteries such as NiCd and NiMH.

5. Quick charging: Li-ion battery is quicker to charge than other rechargeable batteries. It actually takes a fraction of a time to charge when compared to counterparts.

6. High open-circuit voltage: Li-ion battery has a chemistry that results in higher open-circuit voltage than other aqueous batteries such as lead acid, nickel-metal hydride, and nickel-cadmium.

7. Longer lifespan: Li-ion battery can typically handle hundreds of charge-discharge cycles. Some lithium ion batteries loss 30 percent of their capacity after 1000 cycles while more advanced lithium ion batteries still have better capacity only after 5000 cycles.

General disadvantages of lithium ion battery

1. Expensive: Li-ion battery is expensive to manufacture. In fact, the total product cost of this battery is around 40 percent higher than nickel-metal hydride battery. Take note that this battery needs an on-board computer circuitry to manage and ensure that voltage and current are well within the safe limits. This circuitry makes it more expensive.

2. Sensitivity to high temperature: Li-ion battery is susceptible to the downside of too much heat caused by overheating of the device or overcharging. Heat causes the cells or packs of this battery to degrade faster than they normally would.

3. Aging effect: Li-ion battery will naturally degrade as soon as they leave the factory. This means that it is not completely durable despite longer charge-discharge lifecycle because of this normal degradation that transpires whether consumers use them or not. Storage in a cool place at 40 percent charge reduces the aging effect.

4. Deep discharge: Li-ion battery has low self-discharge. The general integrity of this battery remains intact even if partially discharged. However, deep discharge or when the voltage of a lithium ion cell drops below a certain level, it becomes unusable.

5. Safety concerns: Li-ion battery may explode when overheated or overcharged. This is because gasses formed by electrolyte decomposition increases the internal pressure of the cell. Overheating or internal short circuit can also ignite the electrolyte and cause fire. This risk might also subject li-ion batteries to transportation restrictions, especially when shipped in larger quantities.