Battery heating issue
I don't know if you can prevent battery from heat because heat you're talking about is ambient temperature but I can suggest these :

1)You can add passive cooler to battery (Like aluminum heatsink ) 

2)You can add simple insulation plate between battery and heat source but keep in mind battery produce heat too , so leave space for that or add extra cooler

3)I'm not a expert but I don't think 45 degrees much for lithium polymer battery so you can try to remove battery charge's temperature module 

If you can add simple schematic , we can solve your problem more precisely