my 2001 odyssey keeps killing my new batterys.tests show dead cell in last two batteries.any ideas about what could be doing this and has this happened to anyone out there.?

 

welcome to the forum. when my battery did the same, my alternator/regulator was going bad, there was a rotton egg smell, then the battery went bad. ( Ply RR )

 

Can you recharge the batteries ? I mean out of the car with a charger,if so as Doug says it most likely is the Alt.or voltage regulator,not sure if they are seperate or if the reg is in the Alt. Good luck.

 

if the cell is dead because it is dried out then there is a great chance the regulator is bad and overcharging the battery.
the terminal voltage of the battery should be about 13.6V when fully charged and no more than about 14.5V when charging.

If the cell is not dry then the issue is more likely a defective battery or u drive ur vehicle over some very rough roads. The possible cause of the dead cell is being shorted by metallic debris at the bottom of the plates which doesn't normally happen in young batteries.