What battery charger?

Westyfield2

Westyfield2

Westyfield2

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'afternoon GD.

We all know and rave on about the Sanyo Eneloop rechargeable batteries, and the new improved Eneloops are even better. That I'm not questioning :cool:.

However to recharge rechargeable batteries one needs a charger :p. And that is what I don't have a clue about! :confused: All I know is the obvious, you want it to be smart enough that is charges up the batteries and then switches to trickle charging them once they're full instead of trying to continue charging and damaging the batteries. Apart from that, I'm clueless. Are all chargers born equal?


So yeah, GD spec me an AA battery charger plox.
 
Are all chargers born equal?
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Absolutely not.

You're using the best batteries - why not invest in one of the best chargers? The MAHA MH-C9000.

We all know and rave on about the Sanyo Eneloop rechargeable batteries, and the new improved Eneloops are even better. That I'm not questioning .
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I've just got 16 of the Eneloop XX cells and they are even better! A bit higher self discharge but they are all coming off the Maha @ between 2450maha and 2480maha after a single cycle.
 
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Westyfield2 said:
Thanks.

<Potentially thick sounding question> Are SuperFast chargers like that 'safe'? I mean isn't gonna kill the batteries or anything is it?
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Fast chargers tend to reduce the battery lifespan a little, but this can vary on how fast the cells are charged. :) None of them are dangerous as if they were they wouldn't be allowed to be sold.
 
hux said:
Im currently trying to find one i know of that's very highly regarded, tricky to find but good, something similar to the maha smart charger.

Found it, technoline bl700

http://www.batterylogic.co.uk/technoline/technoline-BL700.asp
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Too low a charge rate to charge Eneloops.

Eneloops need to be charged at 0.5c or higher (1050mah) else they will miss their termination and be overcharged - shortening their life span. 0.7c would be ideal.

The BL-700 is only capable of a 0.33c charge rate on Eneloops (i.e the charger max selectable charge rate of 700mah).

That's why the BL-700's are hard to find now - they are simply too slow for modern high capacity cells.
 
Aah right, fair enough i had no idea, it was suggested to me a while back, so as you say batteries have indeed come on since then.

Great knowing eneloops have been improved as well, im a big fan of them.
 
amigafan2003 said:
Too low a charge rate to charge Eneloops.
Eneloops need to be charged at 0.5c or higher (1050mah) else they will miss their termination and be overcharged - shortening their life span. 0.7c would be ideal.
The BL-700 is only capable of a 0.33c charge rate on Eneloops (i.e the charger max selectable charge rate of 700mah).
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Oops. Using the Uniross smart charger to charge my eneloops. As a student, can't justify spending £50 on a battery charger. And I don't use the batteries that much anyway so don't charge them that often.
 
Interseting stuff, fed up of replacing the batteries in the kids wii and all the other toys

I took a look at the wii rechargers and dont really see the point in getting something exclusively for these.

So these eneloops look good, but still a little confused about what charger. I was thinking just some Sanyo Enelope branded one or the MAHA MH-C9000 that someone elses mentioned as it musrly be good at 50 notes and display. Whats the real world difference going to be?

Cheers
 
amigafan2003 said:
Too low a charge rate to charge Eneloops.

Eneloops need to be charged at 0.5c or higher (1050mah) else they will miss their termination and be overcharged - shortening their life span. 0.7c would be ideal.

The BL-700 is only capable of a 0.33c charge rate on Eneloops (i.e the charger max selectable charge rate of 700mah).

That's why the BL-700's are hard to find now - they are simply too slow for modern high capacity cells.
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Just had a nose at the maha smart charger, that would be ideal as that has selectable rates from 200 to 2000mah
 
Why not just use the recommended Sanyo charger MDU01. I have 2 of them : Internals disected here.....

http://www.candlepowerforums.com/vb/showthread.php?165664-Sanyo-NC-MDU01-AA-AAA-USB-Charger

And no, all chargers are far from equal. If you look at the circuit board in the post above - this little PCB is capable of the following.

1.) Charging timer / Timer control / Protection timer
A pre-set timer to prevent over-charging which will shorten service life of battery. Charging shall be stopped at the time stated in the manual.
So, for NC-MQ R02, the rapid charge will stop within 140 minutes from start for charging 2 pcs of HR-3U(2100mAh) which take only 105 min of charging time. This function prevents dry cell battery from causing electrolyte leakage.

2.) Peak cut control / Peak voltage control
This innovative technology protects batteries against overcharging by detecting exactly when the battery has reached full charge.
The purpose is to stop quick charging when a battery reached its peak voltage.

3.) Minus delta voltage detection : At the point of full charge, battery voltage will show a small but distinctive drop. When this voltage drop is detected by the minus delta voltage detector, charging, will stop. This is another method to prevent overcharging.

4.) Temperature control for charger & battery :Built-in sensors monitor battery temperature for both charger & battery to prevent over-charging.
5.) Temperature protection for the charger : by Power Control IC.
6.) Temperature protection for the battery : by built-in sensors which monitor the battery temperature to prevent over-charging. When the battery is beyond the specified temperature, charging will be stopped.
7.) Individual charging control : This function monitors the voltage of batteries with different capacities to make sure each one is charged properly.
8.) Non-Rechargeable Battery : Stop charging if a non-rechargeable battery is accidentally inserted.
9.) Protection / Alkaline : When the battery's voltage charged with 190mA for NC-MQ R02 is beyond the specified voltage, charging will be stopped.

This results in my Eneloops being charged perfectle every time. So very happy with it considering it charges of my USB ports and requires little thought.
 
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MikeHunt79 said:
Looks ideal, I'm surprised a USB can supply enough current but that charger seems to do the business...
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It can't - if you read the specs it can only provide 450mah to each channel if charging two batteries, which isn't high enough for eneloops.

Even if using only one channel, it still only provides 850mah, which is 0.4c, quite way below the recommended 0.7c - not much of an issue as the timer prevents overcharging but do you really want to wait 5hrs+ for a pair of batteries to charge?

I still find it baffling that Sanyo bundle eneloop cells with inadequate chargers.
 
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Why do you think Sanyo's own charger is inadaquate ? Do you have one - or access to your test results once you charged your own Eneloops ? Why do you think a cell at 96% capacity is poor ?????

We all know USB can only supply the 500-900mA - but this is quite sufficient in this case - where the cells are SUPPOSED to be slow charged and not juiced up quickly.


And why is the length of time it takes to charge batteries an Issue when they hold their charge so well - Surely that's one of the main points of it. I don't mind waiting 5hours to charge 4 of these in sync off my very good Eneloop USB chargers - because I now have about 30 of them (all charged and waiting/ and in virtually everything that takes batteries around the house - with the C & D adaptors) - and they all charge to full capacity all of the time.

More Here :

http://www.candlepowerforums.com/vb...-problem-with-Eneloop-AA-batteries-and-BC-900

The Sanyo Reps will recommend only Sanyo chargers for a reason..... and It's not just becasue they are made by Sanyo. They will explain it all if you are really interested.

Sanyo recommends that Eneloops aren't fast charged due to their chemical composition. They also recommend at least a 2 - 4 hour charge. The reason being that the batteries are sealed differently and heat up differently under fast charges. And most importantly - The Eneloop warranty is useless if you have charged them with anything other than an Eneloop charger.
 
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Blimey, there's some real knowledge here :). Somehow I managed to pass A-Level Physics and still barely understand electricity :p.

That MAHA MH-C9000 looks good :cool:. Are there any ones similar to it, or is that the one to get?

With the MAHA, and others, having selectable charging rates from 200 to 2000mAh... how does one know what charge rate to select?
 
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All NIMH's should be charged as close as possible to a 0.7c charge rate. c = capacity. So a 2100mah cap cell should be charged at 1470mah or as close to it. A 2500mah cell @ 1750. A 1000mah cell @ 700mah and so on.

Different chemistries have different charge rates (and discharge rates).
 
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