Leading-edge technology makes rechargeable D batteries ideal for the most advanced high-drain devices. These include digital cameras, personal digital assistants (PDAs), handheld electronic games, portable CD players and palmtop computers. When not in use, they can hold their charge for up to 12 months. These batteries can be recharged hundreds of times. For best results, pair your Recharge batteries with Energizer chargers (sold separately). Since these batteries are both renewable and reusable, they are both a good economic and a good environmental choice.Leading-edge technology makes rechargeable D batteries ideal for the most advanced high-drain devices. These include digital cameras, personal digital assistants (PDAs), handheld electronic games, portable CD players and palmtop computers. When not in use, they can hold their charge for up to 12 months. These batteries can be recharged hundreds of times. For best results, pair your Recharge batteries with Energizer chargers (sold separately). Since these batteries are both renewable and reusable, they are both a good economic and a good environmental choice.