It’s a fixed address, so you’ll either have to use a software I²C library (.e. softi2c) to have things on a physically separate set of lines, or you’ll have to switch between devices. There’s specialized I²C multiplexers, see e.g. http://www.kerrywong.com/2012/10/08/i2c-multiplexer-shield-testing/. You could also try making your own guage using a chip that does have selectable/settable addresses (I’m assuming they’re out there).
Any particular reason you’d want to have, and monitor, more than 1 battery on the same system?
