[lincpimp]

I know using something like a123 cells for a car battery has been discussed, but I wonder if I could make a batt for my zx12r with a123 cells.

Currently I have a agm 14ah 12v battery in there. Not sure what the starting current demands of the engine are (1198cc 4 cyl with 12:1 compression) But I figure a 3-4p setup should work. Not quite 14ah with a 4p (6p would be closer) but I am not sure if I will need the extra capacity as the c rating is much higher on an a123 cell so starting should not be an issue. 4p gives 9.2ah, and at 25c discharge (pretty sure I remember a123 being able to handle that without dropping below 3v per cell) that is 230 amps.

My question is, how many cells in series should I use? 4s sounds about right, 3.3v nominal would be 13.2v and fully charged the voltage would be around 14.4v which is about what a std 12v car battery gets to.

Also wondering if the stator on the bike would cause charging issues? I know a123 cells are pretty good about being charged quickly and discharged low, but can they handle a possible overcharge? Not sure what the stator puts out, but I am sure it is around 12v. I can test this when I get the bike running tomorrow.

Also, a 16 cell a123 pack will be much smaller and lighter than the stock batt, and free up some space. Since the batt is housed in the center of the frame (weird monocoque design ) will I have heat issues with the a123s? Not much (if any) airflow around the batt in the stock location.

So any info would be greatly appreciated, I know we have some diehard a123 users here, so I guess you guys will tell me if I am barking up the wrong tree.