[WMBP]

After reading many recommendations of eneloop batteries in this forum, I bought some earlier this year. They really do seem to be worth the extra money. But now I've worn out the couple sets that I purchased and I need to recharge. My problem is, I don't know whether the AA chargers I have already will work with the eneloops.

The eneloop batteries say, on the side, "Charge only with a Sanyo specified charger." It also says, "HR-3UTG 1.2V Typ. 2,000mAh, Min. 1,900mAh."

I don't know what to make of most of that. I have a couple of different Energizer (Everready) chargers. The model that appears to me to be the "best" describes itself thus:

NiMH-NiCd Battery Charger
Class 2 Battery Charger
Model CHM24
Output: DC/CC 2.8V ~ 140mA x 2

Will this charger work with the eneloops? Or do I need to buy a new charger for the eneloops?

Thanks in advance to all the battery experts here.

Will

[SOldBear]

The eneloop batteries say, on the side, "Charge only with a Sanyo specified charger."

If Honda had its way, I'd have to put Honda air in the tires. When I drive my Honda to work in the morning, I'd drink Honda coffee and eat Honda donuts

You don't need Sanyo charger for Eneloop batteries.

Some chargers are better than others. But there's nothing special about Sanyo charger.

[Nesster]

The eneloop charger is a plain charger, but not a rapid type. You might use that as a guide - any charger works...

[X Man]

Right on, SOldBear! That's hilarious!BTW, I can't seem to find any Honda coffee around here, any ideas?

To the OP, I use a Panasonic BQ-390 Smart Charger to charge my Eneloops and it works flawlessly.

Regards,
Mike

If Honda had its way, I'd have to put Honda air in the tires. When I drive my Honda to work in the morning, I'd drink Honda coffee and eat Honda donuts

You don't need Sanyo charger for Eneloop batteries.

Some chargers are better than others. But there's nothing special about Sanyo charger.

[soccerjoe5]

Best chargers in the world: Powerex, Ansmann and LaCrosse. Smart chargers that'll keep your batts at their best

Sounds like an ad

[WMBP]

If Honda had its way, I'd have to put Honda air in the tires. ....
You don't need Sanyo charger for Eneloop batteries.

Some chargers are better than others. But there's nothing special about Sanyo charger.

OK, thanks. I've plugged 4 eneloops into my charger to prep for a shoot tomorrow and I trust that they'll be fine.

The eneloop charger is a plain charger, but not a rapid type. You might use that as a guide - any charger works...

Thanks. I've heard somewhere that the slow chargers work better and/or do less harm to the battery over the long term. Is that right?

Will

[WMBP]

Mike (X Man) and Diego (soccerjoe5) both have specific brand recommendations. Mike likes the Panasonic BQ-390 Smart Charger; Diego likes Powerex, Ansmann and LaCrosse. What's the advantage of one of these recommended brands?

Will

[jimH]

In talking about battery chargers, I've read about smart chargers that will first discharge all of the batteries in the charger, then proceed to charge all of them at the same rate. This apparently will prevent overcharging those with a partial charge an also will prevent a charge memory by first doing a complete discharge before charging, thereby using all of the battery's capacity.

Additionally they have a function to recondition batteries by charging, discharging and recharging several times to get them back into shape again. Anyone have any knowledge on the subject?

jimH

[davek]

Although this question has been anwered, I just though I'd through in an additional confirmation. I've been using my Panasonic charger with Eneloops for over a year and half now, with no apparent negative effects.

The "eneloop" chargers are slow chargers... they can take +5 hrs to charge the batts...
Is there a reason why Sanyo is selling 5hr chargers with their batteries? Of course there is. They know that fast chargers are not good for their batteries. Otherwise they would package them with 15min chargers... they would sell even better if folks thought you could charge them that fast.

Can you charge them with fast chargers? Of course you can. Just not the best idea.

Any of the slow chargers will work, the smart chargers are better as mentioned, as they charge individual cells, and you can choose to drain before charging. And even select drain and charge rates if you choose too.

Now I am gonna have some Honda coffee.

[WMBP]

OK, couple of interesting suggestions about what the "smart chargers" do.

But what I'm wondering now is, do they really matter to eneloops as much as they might to my more ordinary Energizer rechargeables? I gather that the eneloops are "smart batteries" - that they don't lose power by sitting around at least not at the same rate as ordinary batteries, and that they don't suffer from the memory effect either. So is a smart charger as important for eneloops as it might be for mere mortal batteries?

It looks like I can buy a Sanyo charger PLUS another 4 batteries from under $20 from Amazon and I think I'll do that. That would give me 12 eneloops which should keep me going a while.

But I'm still curious about the smart chargers.

Will

[breischl]

I have been using Eneloops for a while now. I've put them on a garden variety quick charger with no problems, so I wouldn't worry about it too much. It may not be ideal over the long run, but it certainly won't make them explode or anything.

I also have a LaCrosse charger of some sort (BC-900? can't remember just now). I would recommend it if you use lots of rechargeables.

It does do a discharge-then-recharge cycle as someone mentioned, which helps keep batteries performing well. It can also do multiple cycles of that to rejuvenate old batteries. I did a refresh on a couple of really old Sony chargeables I got with a P&S in 2002. It boosted their capacity back to about 90% of rated, from <50%. So it does seem to really help.

It will also tell you how much charge each battery can take. This is helpful because sometimes one battery in a set will go bad. If you know which one it is you can just replace that one, instead of the entire set.

[Quension]

Eneloops are still just NiMH batteries and can be charged by any NiMH charger.

The two most important things you want in a charger is the ability to charge cells individually/independently, and the ability to stop when a battery is full. You should be able to put one battery in any slot and have it be charged until it's full, at which time the charger will stop. A less intelligent charger will only charge 2 or 4 batteries at a time, which can cause problems at both ends of the spectrum: a single battery may be overcharged, significantly shortening its life; a single battery may be undercharged, and when you use it in a device with other fully charged batteries it may become "too empty" first and be permanently damaged by the others that still have a charge. An even less intelligent charger will use a timer instead of sensing when a battery is full, pretty much guaranteeing it will be overcharged. A just plain stupid charger will never stop and is a fire hazard; it boggles the mind that these pieces of junk are still sold.

Rapid chargers wear out batteries faster. Advice for the "right" charge rate varies, but in general anything that charges a battery in less than about 1 hour is considered harmful, 2 hours is considered okay but not great, and 4 hours seems to be a good time. Many chargers are sold by time, but that isn't an accurate rating, since battery capacity varies. Eneloops have a capacity of 2000mAh (milliamp-hours). If you charge one at a rate of 2000mA, then it will take 1 hour to charge; 1000mA will take 2 hours, etc. Look for the charging current and battery capacity numbers and do the math yourself to see how long it will take.

A related issue is that charging them fast makes them heat up, so there's a greater risk of fire if something goes wrong. Smart rapid chargers have temperature sensors and will cut power if a battery gets too hot.

While NiMH batteries don't have a "memory" per se, they do decrease in capacity over time. Smarter chargers have a "refresh" function, which completely discharges and then charges a battery repeatedly until it has regained maximum capacity. There are many stories of this process restoring tired batteries to a usable state again (albeit not quite as good as brand new). Given a gentle charge rate, this is something that can take several days to complete.

Smarter chargers also have a function to discharge a battery completely before charging it again normally. I have not seen any concrete information about whether this keeps batteries at top capacity longer compared to normal use and a plain charge, but presumably it has some benefit.

I like the LaCross BC-700 and BC-900 as advanced chargers. Armed with some basic knowledge, they're straightforward to use, and fairly smart.

One smart charger with no advanced functionality is the Duracell CEF23 (CEF23DX2 / CEF23DX4). It only charges, no discharge or refresh functionality, but it's intelligent enough to handle batteries independently, is gentle, and has a temperature safety. It's also cheap and simple.

[WMBP]

Eneloops are still just NiMH batteries and can be charged by any NiMH charger.

The two most important things you want in a charger is the ability to charge cells individually/independently, and the ability to stop when a battery is full. .....

This list needs a way to flag certain responses as exceptionally good. I have bookmarked this one for future reference.

Thanks, Quension. My knowledge about rechargeable batteries just grew ten-fold.

Will

[Tyama]

Will,

If you're a Costco member they have a Sanyo Eneloop package with 8 AA, 2 AAA, and a charger for ~ $20 $29 minus $10 off instant savings. I saw this on Sunday here.

Terry