Enloop Battery for Yaesu
You get what you pay for. This is an expensive battery, but it is worth it. ENELOOP batteries are made by Sanyo and are the best rechargeable batteries on the market. These batteries maintain their charge for 1 year. After 2 years, they only lose 10% of their charge. After 3 years, 75% of the full charge remains. However, the most important quality of these batteries is that they have no memory effect, which means you can charge them before the battery is entirely run out and there will be no loss in the battery's capacity. This way, you can always keep your radio charged up and not worry about ruining the life of the battery. Also, these batteries can be charged up to 1500 times. So, you will likely never need to replace a battery again. Eneloop batteries also work better than other rechargeable batteries at freezing temperatures, which is a good thing for those flying high altitude.