A lithium-ion battery or Li-ion battery is a type of rechargeable battery that works through the movement of lithium ions from the cathode to the anode when charging, and from the anode to the cathode during discharge. Similar to other batteries, electric current is produced from the chemical reactions between the cathode, anode, and electrolyte.
There are different types of Li-ion batteries based on the materials used to make the lithium-based cathodes and the carbon-based anodes. Note that these materials determine the performance and capacity, as well as the cost and safety of the particular type of Li-ion battery. For example, a variant with cathodes made of lithium cobalt oxide has a higher charge capacity but has poorer thermal capacity than standard Li-ion batteries. Another variant with a cathode made of lithium iron phosphate has four to five times longer charge-discharge cycles and a more expansive operating temperature range albeit a lower energy density.
Lithium polymer is another variant, which uses porous or gel-like electrolyte. Nonetheless, despite the different characteristics of the different types of Li-ion batteries, they still share commonalities or general characteristics that give them collective and generalized advantages and disadvantages over other rechargeable batteries.
Pros: Benefits and Advantages of Lithium-ion Battery
1. Better Energy Efficiency
The main advantage of lithium-ion battery over other rechargeable batteries is energy efficiency. This advantage stems from more specific advantageous characteristics to include having a higher energy density relative to its physical size, a low self-discharge rate of 1.5 percent per month, and zero to low memory effect.
Other types of rechargeable batteries have lower energy density than Li-ion battery, thus making them unsuitable for energy-intensive applications. Furthermore, batteries based on nickel-metal hydride have a 20 percent self-discharge rate per month while nickel-metal hydride rechargeable batteries such as NiCd and NiMH have a memory effect that results in the reduction of their maximum charge capacity when repeatedly recharged after being partially discharged.
2. Longer Lifespan
The lifespan of rechargeable batteries is primarily defined by the charge-discharge cycle they can handle. Lithium-ion batteries can typically manage hundreds of cycles while mid-grade variants can handle 1000 cycles before losing 30 percent of their original maximum charge capacity. More advanced Li-ion variants can retain their capacity up to 5000 charge-discharge cycles.
It is important to note that charging a Li-ion battery to 100 percent after being partially discharged does not count to a single charge-discharge cycle. A single cycle will only count if more than half of the battery was discharged before recharging it to full again. Devices such as the MacBook line of laptops from Apple are recommended to stay plugged into a power source as much as possible to maintain the lifespan and charge capacity of their Li-ion batteries.
3. Faster to Charge
When compared to other types of rechargeable batteries such asNiCd and NiMH or rechargeable alkaline batteries, lithium-ion batteries are faster to charge. Depending on the hardware specifications of a particular device that uses a Li-ion battery, as well as the actual mAh capacity of the Li-ion battery, a full charge can take one to two hours while other rechargeable batteries with similar capacities might take half or twice as long.
Developments in onboard power management technologies have further paved the way for the introduction of quick or fast charging features. For example, semiconductor manufacturer Qualcomm has introduced the proprietary “quick charge” technology in several Android smartphone devices that enable li-ion batteries to reach full charge twice as fast than the standard rate of the USB interface.
4. Smaller and Lighter
Another advantage of lithium-ion battery is that it is smaller and lighter than other types of rechargeable batteries, especially when considering charge capacity. Remember that Li-ion batteries have higher energy density relative to its physical size than their non-lithium counterparts. Hence, when compared to other rechargeable batteries, Li-ion batteries have higher capacity without being too bulky.
The portability of Li-ion batteries makes them suitable for portable consumer electronic devices, such as smartphones and ultrathin laptops, in which physical specifications such as weight and dimension are considered essential selling points. The same compactness of Li-ion batteries, in addition to their energy efficiency, make them ideal for use in hybrid and electric vehicles.
Cons: Limitations and Disadvantages of Lithium-ion Battery
1. Expensive to Manufacture
A notable disadvantage of lithium-ion battery is its high production cost. Note that producing this battery is around 40 percent more expensive than nickel-metal hydride battery. One of the factors that drive its production cost is the need to include an expensive on-board computer circuitry to ensure that voltage and current remain within the safe limits.
It is also important to note that high-performing li-ion battery variants use rare metals such as cobalt and nickel that are scarce and thus, expensive to source. Growing demand for these batteries has quadrupled the wholesale prices of rare metals over the recent years, thus hampering the development of other Li-ion battery applications.
2. Aging Effect and Deep Discharge
Like any other rechargeable batteries, lithium-ion batteries degrade as soon as they leave the factory whether they are in use or not. This is called the aging effect. Thus, despite having a higher charge-discharge cycle than its counterparts, it is not entirely durable. Extending the lifespan of this battery requires proper storage, particularly in a cool place at 40 percent charge.
Remember that Li-ion batteries have low self-discharge. Their integrity remains considerably intact even when not in use as long as they are properly stored with a suitable amount of charge. However, these batteries are vulnerable to the phenomenon called deep discharge. When the voltage of a particular Li-ion battery drops below a certain level, it becomes unusable.
3. Safety Hazards
Another disadvantage of lithium-ion batteries is their susceptibility to fire hazards due to a particular cause of overheating. They may explode when overheated or overcharged due to the buildup of gasses and subsequent increase in internal pressure from electrolyte decomposition. Furthermore, overheating or internal short circuit can ignite the flammable electrolyte, thus leading to explosion and fires.
Note that a Li-ion battery is sensitive to too much heat. Consistent exposure to thermal stress due to overcharging, improper storage, and internal hardware failures can shorten its lifespan. The cells and packs in this battery degrade faster under intense heat, thereby resulting in loss of battery integrity. It is also worth mentioning that overheating causes specific damages to different electronic components of a hardware or device.
