Noob question about Eneloops

Farhad Gulemov

Newly Enlightened
Joined
Nov 23, 2009
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48
Hi

I bought 8 Ni-MH rechargable Sanyo Eneloops ( 2,000 mAh) for my Fenix TK40. I got a pack of 4 and a set of 4 rechargables and one battery charger. My question:

Since the charger only as 4 slots, can I use another (Energizer) charger for "regular" (non-Eneloops) batteries to charge my 4 remaining Enelooops, or must these batteries be charged with a Sanyo charger?

Thanks!
 
The sanyo charger is nothing special, you'd probably be best off buying a good charger, but any other charger you have should be fine.
 
Yep they will charge fine in any NIHM charger.... Actually I use an old trusty Rayovac 1 hour charger I have since the Sanyo charger takes hours to recharge..
 
Watch the current on that 1 hour charger. Does it terminate charging based on time or delta V? Either of these factors is critical to knowing whether or not you're shortening the life cycle of your Eneloops by overcharging them. Does your 1 hour charger have a fan? If not it might be a good idea to get one on them while charging. Also, does your 1 hour charger use independent circuits or is the delta V/time determined by an average of two cells in two bays? An easy answer to that question (at least) is will your charger work with only one cell in it? Will it work with only one cell in each bay (one cell in the charger trying each bay consecutively)? If so, it's likely that the charger has independent channels, which is a mark of higher chargers and alleviates the requirement of having two matched batteries charging.

Example: If your charger only works with two batteries in it and you put one that has 90% of a charge and another that has 20% charge in it, the charger (with no independent channels) takes the average of 55% and puts in the equivalent of 45% of a cell's capacity into both! This overcharges the first cell by 35% and leaves your second cell, which started with 20%, with only 65%! Think back to school, 65% is a "D." I want my rechargables to come out of my chargers with an A+!

Of course, for about $30, you could get a Maha C9000 which babies and coaxes energy out of the most tired cells and maintains new ones much longer.

On another note, what's with all of the battery questions in the wrong thread lately? Not that I mind answering them or participating in the conversations, but I got all of my knowledge (limited though it may be) from reading the battery forums. Is it common to just post in the most populated area regardless of which subject your topic is related. If you're not a patient person, just subscribe to the thread and check your email. Also, search is your friend.
 
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that "charger" coming with the Eneloops is crap, starting with it to only charge 2 cells at a time and not the individual cell

throw it away and get a decent charger! You dont get anything out of the LSDs, when the charger is a bad one.
 
I just edited my last post to include what I think is an illustrative example of how bad these dual-bay chargers are. And for clarification, it's not that there are two or four bays in the device, it's that they're wired together instead of independently.
 
that "charger" coming with the Eneloops is crap, starting with it to only charge 2 cells at a time and not the individual cell

throw it away and get a decent charger! You dont get anything out of the LSDs, when the charger is a bad one.

How many charges might it take for a cheap 2 cell at a time charger to permanently ruin batteries?
 
Every Eneloop package I've ever gotten have come with the instructions "charge two cells at one time." There was also some vague wording about how the batteries should have the same amount of charge left in them (in other words, matched). Too much work. I wonder how long it's been since Sanyo stopped packing those independent channel chargers in with their batteries.

Also, the damage is progressive. The longer it goes on, the worse it is. Some chargers can lessen the impact so if you're asking this question wondering how long you've got before ruining your investment in the more expensive rechargables instead of going for lithium primaries, I'd say you need to protect your investment. The sooner you get a better charger, the better.
 
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For those that aren't in a position to upgrade their Sanyo MQN06U series charger, please note that you can bring your cells back into balance by utilizing the charger's trickle charge function.

Simply leave the charger powered on for a period of hours following its primary charge cycle. How many hours is dependent on the initial state of imbalance, but in a worse case scenario, I wouldn't hesitate to allow the charger to remain powered on for up to 24 hours including the primary charge cycle.
 
It's generally OK to charge batteries in a "pair" charger. After all, many hobbyists charge NiMH packs with 6 or more cells in series. You need to make sure you keep and use pairs together, so that both are equally discharged before you charge them. Also, from time to time you should do an equalizing charge as Bones suggests, by leaving them on the charger for a long time after the main charge finishes.

To call the MQN06 "crap" is vastly exaggerating the true situation.
 
It's generally OK to charge batteries in a "pair" charger.

Since I will be using thse Eneloops for my Fenix TK40 and nothing else, they will most likely discharge in a very similar fashion. Hence, this charger should be ok (I suppose).

I would love to get a Maha C9000, but since the cheapest price I could find so far was about 45 bucks, that is more than what I can afford right not (TK40: 140$ + 8 Eneloops & charger: 30$ + leather lanyard: 20$ - I am maxed out:()

Thanks for all the replies! :thumbsup:
 
I understand your financial prediciment with your light. That's pretty well known around these parts. :)

When you do have a few extra bucks, and are thinking about upgrading your charger, I personally would look into one of the Maha 800 series 8 bay chargers. You can't beat charging all 8 cells of a battery set at the same time, with the same charger. This prevents, among other things, 4 cells having sat around a few hours, while the remaining 4 are being charged. While the imbalance is probably small, it's important to note that NiMH cells loose their charge at the highest rate, right after you take them out of the charger (including LSD's).

The Maha C-9000 is a great analyzer, but in your case, the 800 series would probably negate the need for one. They are much simpler to setup and use, as well.

There are other 8 bay chargers that would probably work, but the Maha's seem to be the best IMO.

Dave
 
The Maha 800 series look very good indeed, but that's still another 52 bucks (on Amazon). I will set some money aside and, hopefully, will get that in the future. Thanks for the pointer!
 
It'd probably work. I'd say it's about half the charger a Maha 800S is. You get what you pay for, pretty much.

The charge rate is good for AAA's. I'd prefer about twice that for AA's, so as not to worry about missed terminations.

Dave
 
WHAT!!!!
You all think that crap charger (as it is crap) does not wire the 2 cells to be charged together in series,
You think the 2 cannels/batteries are put together in parallel?

now, then I have to change, that charger is not crap then, it is CRAP!!!!
You use Eneloops to "get the best out of the Ni-Mh cells" and then use a bad charger knowing it is bad: simply stupid
(if You had a charger that does give the energy stored in the cells when doing the discharge cycle, You would be surprised by the differences. Especially with a multicell-high draw light like the TK40)


that titanium 8-channel charger looks good, also not expensive.
 
Eneloops at 3-$4 a pop add up investment wise. Caring for them best as possible makes sen$e. After long deliberation I sprang for the C9000 on a tight budget and have not regretted it once. Buy cheap, buy twice my father always told me...
 
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