The apparent battery life might be distorted a bit by my work and gaming machines being separate, but the mouse in my gaming setup (Logitech G604 Lightspeed) gets months of life out of a single Eneloop Pro rechargeable AA when using its USB RF dongle. It was a bit of a surprise with my last wireless mouse having been the mid-2000s Logitech MX1000 which had an integrated battery and needed to be docked a lot more frequently… it's fuzzy but I think I might've gotten a week out of it on average.