This is a LIFEPO4 setup. The red charger is pure goodness. Plug the little gharger cord into it & everything is checked & fully charged & then it TURNS OFF.

At 71 this is love. Peaks to 100 % & no overcharges.

No fires on over discharges & recharges.

The C ratings are 30C with a LITTLE voltage drop.
2 sizes. this is the 1100 mahr..........also a 2300 mahr size..........HARD METAL cases.
These are from Black & Decker battery packs bigger units a DEwalts power pack.

NOT cheap. But they have NO self run down when stored for 6 months. Hundreds of full power cycles.