Originally Posted by HiYoSilver
I don't know. Ask slvoid. The other key variable is low temps. at 5F, a NiMH battery will operate at 35% power and life while a LIIon will be at 92%. It's a sharp curve, and above 50F, they are the same. So if ride in cold temps, may want to spend a few more bucks. Other key variable is Liion last 3 years from date of manufacture, and NiMH last about 5 years. Similar to a car battery. Even though they are the same at about 500 recharge cycles, unless you ride a lot at night, you might be caught by the lifetime limit before the recharge limit.
The Li Ion has a much lower self discharge rate during storage. I have one that is rated about 10% loss a year. NiMh can be 10% loss the first day. You need to keep NiMh charged to get the rated life out of it.
Some light systems say once a month all year. The Li Ion has less memory problems too. Even though NimH is not too bad and can be retrained. The Li Ion is more $$.