you can zap the batts to improve the voltage and lower ir.
however, bear in mind that the performance which you can extract from each pack ultimately comes from the amount of effort you put into the maintenance. you can have the best batts but if you do not take proper care, it's money down the drain. (unless of course you are a top sponsored driver who can gets a new pack for every race). in some ways, the better the pack, the more care it needs to maintain the voltage/ir numbers.