Building a pack

[westernshooter]

update. the two cells are definately at zero. however, dumb me. the 20 amp fuse i replaced coming off the pack had blown. with the two dead cells the pack still comes up 41.7 volts. guess I should change those two. maybe thats why my speed and distance dropped significantly who knows how long the have been weak. any way. replaced the fuse plugged the mosfet in and POP. immediately blew the fuse...hmmm. now what. can this be fixed or replace the mosfet?

 

[westernshooter]

update. the two cells are definitely at zero. however, dumb me. the 20 amp fuse i replaced coming off the pack had blown. with the two dead cells the pack still comes up 41.7 volts. guess I should change those two. maybe thats why my speed and distance dropped significantly who knows how long the have been weak. any way. replaced the fuse plugged the mosfet in and POP. immediately blew the fuse...hmmm. now what. can this be fixed or replace the mosfet? Where can I get the same mosfet or what will work with this range so I can continue to use when I upgrade my Battery?