NiMH Hypercycle

[koala]

I was searching for some micro lithium batteries to go into my pendant light :naughty: and some how manage to stumble across NiMH batteries in Toyota Prius hybrid vehicle. I soon forgot about my micro lithiums as it becomes more interesting as I read on the report regarding shallow discharges in the Prius. This is the first report I read that NiMH can last 300,000 cycles if discharged depth is only 10% of it's capacity. Perhaps the Prius NiMH is a specially formulated battery.

Prius NiMH Hypercycle post at priuschat.com

It reminds me of the Saft Space VES 140 Lithium Ion batteries which claims to last 70,000 cycles at 20% depth of discharge.

 

[FroggyTaco]

I remember reading in Car & Driver that they only charge the pack to 85% full & only let it drain to about 50-60% capacity to maximize the lifespan of the batteries.

 

[WDG]

There's a post somewhere here in CPF that discusses this, though I can't recall which one, right now. Apparently by limiting both charge and discharge, the cells never get really stressed, so last much longer. Disadvantage is the vehicle is carrying around a LOT more charge capacity than it is allowed to use.