EneloopPanasonic K-KJ87MCA4BA Individual Battery Charger with Portable Charging Technology and 4AA Rechargeable Batteries, White

Really happy with this charger and battery set! The charger is simple — just pop the batteries in and it shows you when they’re done. It charges pretty fast too.

These batteries have really impressed me and I have phased out all non-Eneloop batteries in my house. They're way better than any Energizer or Duracell I've ever used. I wish Panasonic would increase their marketing for these so people can be freed from the money-squeezing grip of normal batteries!Pros:- better voltage curve than normal alkaleaks, so they last longer and perform better with a similar mAh capacity- can be recharged more times than most people will ever recharge them- compatible with basically any device that takes button-top AA batteriesCons:- charges via micro-USB

It does a nice job of charging batteries that are 0-2 years old without heating them up too much which will help them live longer. You can take out a battery when it's finished and put another in while it's still charging some others and it doesn't mess up the charge of the ones you keep in.It's super picky about charging batteries that are older than 2 years without really even trying, despite the fact that it isn't a fast charger at 500mA for 4 batteries, so they should be able to handle it. It didn't like most of my batteries, rejecting them with a blinking red light within a few minutes at most. Of course, I had another charger before I got this one and have been charging and using the batteries I haven't pitched yet, so they have to be good enough. I use my other charger more than the Panasonic, even though I want to like it more. I use it for the new batteries.If a battery is 85-90 full and you try to charge it, it will charge it for about 2 minutes and then say it's full. Then you'll put it in a light that uses 4 batteries and the other 3 identical, but fully charged batteries will try to reverse charge it when it runs down because it wasn't really full and is flat dead way before the others. In a case like this or with older batteries you can run the battery down in a light or something for few minutes and put it back in and it will charge normally. If it doesn't that battery is too old for this charger or it's just a bad battery. I just put any nearly full batteries I want to top off a little in my old charger and they finish about when I would expect.You can run something off the USB port when it's full of batteries and the lights change to show how much charge is left. They run down quickly, so the charger, the batteries, and the other device together don't seem to be that efficient at it. You would need more than 4 batteries to charge just about anything.

OK -- nuts for batteries.This is the brand you want for consistency.I use Panasonic chargers and several others. Panasonic chargers do not 'push' as much voltage into the state of charge upon completion -- probably this tends to increase battery life. My preferred charger is a MAHA - MH-C401FS . . . if you can still find one -- discontinued. I have three.In any case I slow charge watching for too much heat and explicitly 'rest' and rotate all the batteries in my 'fleet'.When used with a phone a full state of charge is not reachable, even if you swap in another set of charged AAs, but it can keep you going when you are away from alternatives -- while still being available for flashlights and such.When you buy rechargeables -- mark and date them to observe how long a lifetime you are getting for your $$$. Even Eneloops are not perfect.All my AAs & AAAs are Eneloops.In 15 years I 'think' I have only had 2 out of several dozens that have failed.

I love everything about this. The charger is light and very compact: basically the size of a pack of cigarettes. Charging via mini-USB is extremely convenient. No separate power pack to look after. The overcharge protection is a feature I really value. The LED charge-level indicators are useful: Red, Yellow, Green lights -- then off when fully charged. If a rechargeable battery is damaged or just past its lifespan, a flashing light alerts you. Most valuable is that you can charge 1-4 batteries at a time; they needn't be in pairs, like in most chargers. You can also mix AA and AAA in the same charge. What's not to love?

Very satisfied with product and supplier. Delivery on time.

I purchased the charger, along with quite a stockpile of AA and AAA eneloop batteries. After the first batch of AA discharged, I tried charging them... it read them as "bad" batteries with a flashing red light. I tried the AAAs... same thing. I even tried some Amazon brand rechargeables I had, but every single one shows as needing to replace.On top of that, customer support is impossible to contact. The phone number listed here hangs up immediately, and the website it links to said they don't support this product. They gave me the email of another division of Panasonic, which ALSO doesn't support this product! I'm trying their Facebook page, but it's pretty deserted.I wanted to buy the best, so I paid the extra money. Now I just feel scammed.

Works great. I love that I can charge them from a USB port (but that’s the only way for this model so make sure you are not looking for a charger that plugs into an outlet; this one is not it).