Review on Rechargeable AAA Lithium Batteries With Micro USB Charging Port - 1000 Cycle, 1.5V/400MAh - Pre-Charged, 4/Pack by Alexis Jordan

Bought these for my boss who loves to visit inhospitable places across the planet and hates to bring a charger. These batteries do everything themselves - you plug them into a USB outlet and they refill inside of some 90 minutes. One outlet will charge all four of them and they neatly indicate that they are still charging with a fierce red light and will then go dark once full.You have to charge them via the USB - the LiPo charger will not understand how to charge them and perhaps even damage them. They charge quite linearly. You can do half full in some 40 minutes.The energy content is not great and the seller also makes no such claims. They hold .4Ah over 1.5V, some 2100 joules.They do self-discharge rather swiftly, so the "pre-charged" claim will be 80% untrue by the time you get them.They are hence best suitable for heavy use on the go or for constant use. Don't use them to save battery cost on your Bose headset unless you use it all the time.The light indicator is really neat. It's so bright you can operate the batteries in complete darkness, outdoors or aboard a plane. They have good low tolerances and are all quite equal in charge time and capacity. And the fact that they can be fed via an ordinary micro-USB cable is a great feature.