Been looking for a high capacity rechargeable double A batteries in the market that will be use in my 600 EX-RT speedlite for my upcoming wedding coverage and I found this kickass cool design the black eneloop XX Batteries. This battery HR-3UWXB is the highest capacity and lowest self discharge eneloop battery ever produced. The eneloop XX rechargeable battery from SANYO has been designed for professional use.
According to eneloop this is the perfect choice for powering high current consuming devices such as photo strobe flash lights; providing more than twice the number of flashes per recharge in less than half the time compared to conventional alkaline batteries!
SANYO’s engineers developed the eneloop XX batteries to excel in extreme conditions where high power performance in very low temperature environments (down to -20°C) is needed. The eneloop XX Nickel Metal Hydride batteries retain up to 85% of their capacity even after one year of storage.
Unlike regular alkaline batteries which can only be used once and are wasteful to the environment, the eneloop XX batteries can be recharged up to 500 times. They come pre-charged and can be used immediately out of the pack. This battery is made in Japan.