Amazon offers its Prime members the Eneloop AA Rechargeable Batteries 4-Pack with Charger, model no. SEC-MQN064N, for $12.99 with free shipping. (Non-members can spend $35 to qualify for free shipping; otherwise, shipping costs $5.74.) That's the lowest total price we could find by $5. The batteries are purported to be able to be charged up to 1,500 times.