Battery causes device failure

I've posted the schematic a while back. I don't the link. I'm not sure what you mean what I have for the fets? I'm running them both off the same source. I'm only using the mosfet drivers because I can't drive the fets directly.

There is no information in the datasheet about how to use the IC except a few examples for "one-sided" driving.

To me, it would seem the driver should prevent both high and low gate's from being both on as this causes a short... but of course it doesn't.

Well, let's put it that way: If you have large FETs that drive something large and there is nothing that prevents this bridge converter to start with screeching tires (a.k.a. the max juice it can get) then ... kablouie.

There is always a delay in switching FETs so you might have cross conduction for a mighty long time, easily 50nsec per switching event. If the chip specs mention nothing about dead time control you've got to provide your own. But this is unlikely the cause of your problem, it just reduces efficiency and possibly the MTBF of the FETs.

To test for cross conduction hang a 0.1ohm or something into the source-GND link of the lower fet. Connect a scope to that and be prepared for a nasty surprise.