Nimh Batteries with the Radbot 1000
I have been running the Radbot 1000 this year for commuting. It has worked fine but will shut down after 4 or 5 days commuting (approximately 7.5 hours worth) powered by the fairly expensive Energizer Ultimate Lithium's. I have found standard Alkaline batteries don't quite last so long, but they are not as bad as you'd think.
I was hoping to use rechargable Nimh batteries - but they come fresh out of the charger at 1.3V vs. the 1.5-1.6 that the Lithium batteries maintain for several days. Does anyone have experience with the Nihm batteries? I ride in some fairly chilly weather - worst case about -5º F. This year most mornings bottom at about 10º F.
I use the nimh's with my Dinotte taillight & they work fine in similar temps. I can't say that I've tested how long they will last, as I usually just charge them daily. Since Dinotte sent me an extra charger & batteries, I have both the Sanyo Eneloops & the energizers. I can't say for sure, but the Sanyo seems "smarter", the batteries don't heat up and the charger doesn't go by a timer as the energizer instructions said it does, it seems like the sanyo can tell if the batteries are fully charged.
I have run NiMH 1000 mAhr cellls in my two Radbots after testing Lithium, Alkaline, and NiMH.
Link is on the CPF bicycle forum but it is closed for repair at the mo search Radbot 1000 to find the thread, if you are very interested check the data. Short version: NiMH won. Output over time charts provided.
I reported an issue in Another Commuting Thread About lights. My conclusion is to run then no more than 4 hours and maybe adjust the spring contacts especially if bumps seem to shut them down.
On longer rides, I carry spare AA cells in inside pockets in case (and a small screw driver).
They do pull a lot of current and NiMH output drops more at low temps, so YMMV at temps in the -5 range on down.