Tl;dr from author in comments: > The best choice is to avoid disposable batteries where possible and use low-self-discharge Ni-MH cells such as the Sanyo/Panas

Tl;dr from author in comments: > The best choice is to avoid disposable batteries where possible and use low-self-discharge Ni-MH cells such as the Sanyo/Panasonic Eneloop. Even though the upfront cost is higher, it only takes a few recharges (in some cases, less than ten) to be financially (and possibly even environmentally) ahead.