Understanding battery aging in grid energy storage systems

Lithium-ion (Li-ion) batteries are a key enabling technology for global clean energy goals and are increasingly used in mobility and to support the power grid. However, understanding and modeling their aging behavior remains a challenge. With improved data on lifetime, equipment manufacturers and end users can cost effectively select and control batteries. Writing in the Journal of Power Sources, Kim et al. shed light on this issue by investigating the degradation patterns of various common Li-ion cell chemistries under different duty cycles, such as peak shaving and frequency regulation. They present experimental results from a 15-month long campaign, finding that Li-ion phosphate cells degraded the least and that frequency regulation applications degraded batteries the least when normalized with respect to discharge energy. Lithium-ion (Li-ion) batteries are a key enabling technology for global clean energy goals and are increasingly used in mobility and to support the power grid. However, understanding and modeling their aging behavior remains a challenge. With improved data on lifetime, equipment manufacturers and end users can cost effectively select and control batteries. Writing in the Journal of Power Sources, Kim et al. shed light on this issue by investigating the degradation patterns of various common Li-ion cell chemistries under different duty cycles, such as peak shaving and frequency regulation. They present experimental results from a 15-month long campaign, finding that Li-ion phosphate cells degraded the least and that frequency regulation applications degraded batteries the least when normalized with respect to discharge energy.