What are the benefits of using lithium-ion batteries?

There are many tools around us that run on electricity. Taking advantage of the benefit that they are small and powerful, lithium-ion batteries are incorporated into a variety of devices. In particular, products such as smartphones, PCs, and digital cameras became smaller, lighter, and longer lasting after they started using lithium-ion batteries. Electric vehicles were initially equipped with nickel-metal hydride batteries. However, they now use lithium-ion batteries because of their benefits in being powerful and having low self-discharge and because they do not suffer from the non-user-friendly inability to allow top-up charging like nickel-metal hydride batteries.

• Lithium-ion batteries are also used for small home appliances such as cordless vacuum cleaners and irons, vehicles such as electric bicycles and electric motorcycles, and applications such as storing electricity generated during the day using a solar power generation system at home.

• Lithium-ion batteries are smaller and more powerful than other batteries: Secondary batteries that can be recharged and used repeatedly like lithium-ion batteries include nickel-metal hydride batteries and nickel-cadmium batteries in addition to lead-acid batteries. The most obvious advantage of lithium-ion batteries compared to these batteries is that they are small and light, and yet powerful.

• Lithium-ion batteries stand up well to repeated charging and discharging: Lithium-ion batteries do not utilize chemical reactions like other secondary batteries when making electricity. Therefore, compared to other secondary batteries, their electrodes deteriorate less, allowing them to stand up very well to repeated charging and discharging.

• Lithium-ion batteries can be fast-charging: A major feature of lithium-ion batteries is that they can be charged quickly. But fast charging, or charging done in a short time, is something that secondary batteries other than lithium-ion batteries can also do. However, with nickel-metal hydride batteries and nickel-cadmium batteries, it was difficult to determine when charging was finished, so fast charging was not put to practical use. Fast charging of lithium-ion batteries has been implemented because the charger can determine when charging is finished.

• Lithium-ion batteries support wireless charging: Wireless charging, or charging without a charging cable, is also possible with secondary batteries other than lithium-ion batteries, just like fast charging. However, since wireless charging technology was established in 2007, making it a relatively new technology, it was adopted for lithium-ion batteries, which were already expected to become widespread. Research is being conducted into a system that will make it possible in the future to charge electric vehicles simply by parking them in a parking lot.