The solid state lithium ion batteries mainly degrade due to electrolyte decomposition. This process is accelerated at high temperatures and high voltages. Therefore the batteries should be kept cool and not in a fully charged state for a long period of time. Trickle charging at 4.25 V is "deadly". On the other hand the performance of the batteries is much better at higher temperatures and a higher state of charge. For best performance AND good lifetime it is recommended to manage the temperature (warm during use and cool during idle and charging periods) and charge directly before use only. It may extend the lifetime if the cells are charged to 4.2 V or 4.15 V only instead of 4.25 V - but this of course reduces the available capacity.

Tests on other Li-Ion cells have revealed that the capacity is higher for the first 300 cycles if the cell is charged up to 4.25 V. After 500 cycles however, the capacity of the cells only charged up to 4.1 V becomes higher, because of degradation.