The lifespan of lithium-ion batteries
Lithium-ion batteries are currently the best technology available on the market. These high-performance batteries are widely used and highly preferred. Since their inception, they have been the subject of extensive research. Over time, lithium-ion batteries have continuously evolved, with improvements in safety, performance, capacity, and longevity.
With the growing demand for energy and the rapid expansion of the battery market for electric vehicles and energy storage, research efforts are intensifying, driven by significant scientific and environmental challenges. At the same time, new technologies featuring alternative systems, such as solid-state batteries and lithium-sulfur batteries, are emerging, but none have yet reached the stage of technological breakthroughs leading to industrialization.
Lithium-ion batteries offer numerous advantages that explain their development since 1991. These batteries boast high energy density, low self-discharge rates, and a lightweight design, along with excellent lifespan (measured in charge-discharge cycles).
How a lithium-ion battery works
A lithium-ion battery is a device for storing electrical energy by converting chemical energy into electrical energy through the exchange of lithium ions between a positive electrode (the cathode) and a negative electrode (the anode).
When the battery is in use (discharging), lithium ions move from the negative electrode, through the electrolyte, to the positive electrode. Electrons flow from the anode to the cathode via an external circuit, generating an electric current.
With repeated charge-discharge cycles, metallic lithium can accumulate as dendrites (tiny lithium crystals) in the liquid electrode. This lithium becomes unavailable for battery operation, which can lead to performance degradation.
The lifespan of a lithium-ion battery
The lifespan of a lithium-ion battery depends on its manufacturing quality, the type of device, and the frequency of use.
A lithium-ion battery can be recharged many times typically between 500 and 1000 cycles. A cycle corresponds to a full discharge followed by a complete recharge. A battery is considered at the end of its life when it loses 20% to 30% of its storage capacity. It’s worth noting that a lithium-ion battery continues to age even when not in use.
Temperature can also influence the long-term lifespan of a lithium-ion battery, although it doesn’t affect its immediate performance. Conversely, exposure to cold temperatures can impact a battery’s performance without affecting its overall lifespan.
Optimizing the lifespan of lithium-ion batteries
Simple practices can help extend the lifespan of a lithium-ion battery. Avoid waiting for the battery to discharge fully. It’s recommended to recharge it when it reaches around 10% capacity (or even earlier) to prevent deep discharges. Repeated deep discharges can damage the battery, causing it to age more quickly.
An idle lithium-ion battery wears out faster. Therefore, regular use is advised to maintain its lifespan. If the battery won’t be used for several months, store it in a dry, temperate location, outside its device. Charging it for 20 to 30 minutes once a month can prevent premature aging.