Base space is precious. Better build external batteries on (almost) the same spot. This also should not reveal your base as for the AI they are independent objects. And those are so weak that it's never possible to destroy any UFO before it can reach the base, that only works with Stingray and antimatter missiles. Which means you need to lure the UFO back into firing range many times, and that seems to reveal the base positions (launching and landing interceptors, as with supply ships for alien bases)