I usually charge at 1C sometimes as high as 2c but its rare. they have been stored in my garage which gets hot in the summer. but my air packs are there too and they dont puff. the latest 2 packs I stored in my bedroom to make sure they dont get hot and they still puffed. I really dont want to have to spend over $100 for a 2s battery. where can you even buy a 2s trinity stick pack? its looking like they stopped selling batteries.