Charging lithium-ion batteries to 100% capacity does not provide significant benefits and can in fact reduce their lifespan. Several sources emphasize that lithium-ion batteries do not require being fully charged to maintain health, and charging to 100% puts additional stress on the battery, leading to faster capacity loss over time.
Key Points on Charging Lithium-Ion Batteries to 100%
- Lithium-ion batteries do not have a memory effect, so fully discharging or charging to 100% is unnecessary.
- Charging to full capacity and then discharging to around 50% typically results in a shorter overall battery lifespan compared to cycling between lower charge levels, such as 85% and 25% state of charge (SoC).
- The largest capacity loss occurs when a fully charged lithium-ion battery is discharged deeply; avoiding 100% charge and deep discharge prolongs battery life.
- Storing lithium-ion batteries at 100% charge can cause irreversible chemical changes, such as reducing the ability to dissolve lithium metal during discharge, which accumulates damage over time.
- Lithium-ion batteries can be safely charged at partial levels without damage, offering flexibility to recharge partially as needed without requiring a full top-off.
- While lithium-ion batteries can be fast charged to 100%, this speed and capability don’t translate into a benefit for battery longevity or health.
Summary
Charging lithium-ion batteries to 100% is not necessary and can accelerate battery degradation. For optimal longevity, it is better to charge them partially (e.g., up to 85%) and avoid deep discharges. This practice reduces chemical stress and extends cycle life, although it means using less than the battery’s full energy capacity at each cycle. The flexibility of lithium-ion chemistry allows for partial charging without harm, making it preferable to avoid full 100% charge regularly.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/are-there-any-benefits-to-charging-lithium-ion-batteries-to-100-capacity/
