Charge voltage experiments with lithium ion batteries showing how capacity varies with charge voltage and higher cycle live with lower charge voltage
Do li-ion rechargeable batteries in flashlights discharge gradually like normal batteries (letting you know you should change them) or do they abruptly stop working? - Quora
Lithium-Ion State of Charge (SoC) measurement - Coulomb Counter method - OCV
Beyond Li-ion Batteries: Could These Alternatives Be the Way to Go? - News