# SANYO eneloop charging times?



## Epimetheus (Jun 5, 2010)

I've just bought a Sanyo charger for my (10 No) 2000mAh eneloops. Model MQN04*A* (for Australia).







According to the enclosed instructions, it says that the cells will need charging for an "*estimated*" period of 10 hours. (From fully discharged???)

But the instructions also say that the charger will switch off after "*approximately*" 16 hours as a means of "*protection*" for the cells.

The green LEDs stay on all the time until the charger switches itself off, so it's impossible to tell exactly when your cells are fully charged (other than loading 'em up and checking with a DMM — which is a nuisance), or whether or not you're leaving them to unnecessarily "cook" themselves for several hours more than needed. At the extreme — and depending on the cells' remaining charge — you could be charging them for anything up to 6 hours more than needed, or even up to (say) 10 or 12 hours more than necessary (to top up their charge as needed).

I've also noticed that even at the end of a full 16-hour charge, the cells remain quite hot to the touch, so I'm guessing that it doesn't have any sort of charge-detecting circuitry built-in to discontinue the actual charging process? Presumably, it's still trickle-charging right up to the 16th hour?

Is this an inherent design fault with these Sanyo chargers; will I damage and/or shorten the cells' working life. Or am I worrying about nothing?


----------



## TakeTheActive (Jun 5, 2010)

Epimetheus said:


> *I've just bought a Sanyo charger: Model MQN04A* (for Australia)...


Please post the mA and VDC per channel rating embossed into the plastic charger bottom or SEARCH for and post the LINK to the charger manual (CPF Member *Bones* is usually familiar with 'most' Sanyo Chargers).



Epimetheus said:


> ...But the instructions also say that the charger will switch off after "*approximately*" 16 hours as a means of "*protection*" for the cells......*I've also noticed that even at the end of a full 16-hour charge, the cells remain quite hot to the touch*...


Hot is relative. Once the charger's specs are known, a decision on its quality can be made.



Epimetheus said:


> ...*Is this an inherent design fault with these Sanyo chargers*; will I damage and/or shorten the cells' working life. Or am I worrying about nothing?


Quality varies among manufacturers - meaning one manufacturer may produce both GOOD and BAD chargers. If the cells are exceeding 120°F when inserted EMPTY, I would consider purchasing another 'Smarter' charger. Continued overcharging / overheating will shorten your cells' life.


----------



## fishinfool (Jun 5, 2010)

Since you have eneloops, I would suggest you buy a smart charger like the Maha C-9000. There are other smart chargers that members like and swear by but the C9000 is simply the best and for $48.97 isn't too bad.


----------



## Mr Happy (Jun 5, 2010)

This is a very simple design of charger. It looks like it charges AA cells at 250 mA per channel (it has two channels). This kind of charger relies on the ability of quality cells like Eneloops to absorb a moderate amount of overcharge without being harmed. Once the cells are fully charged they just turn the extra charge into heat, which is why they get warm. If the cells are feeling warm after 8-10 hours of charging you can manually remove them without waiting for the 16 hours to be up. Warm cells are a good sign that charging is complete.

The charger is not the best out there, but it will be satisfactory if you try to charge cells in evenly discharged pairs and if you avoid charging for the whole 16 hours unnecessarily.


----------



## Epimetheus (Jun 6, 2010)

Thanks guys. 

According to the embossing on the charger's case...
Input 240V @ 50Hz
Output 2.4V
250mA (per 2xAA)

I've also checked out a few of Bones' threads — very informative!

All the eneloops are showing (non-loaded) 1.41V hot off the charger.


----------



## mfm (Jun 6, 2010)

Epimetheus said:


> All the eneloops are showing (non-loaded) 1.41V hot off the charger.



They are not overcharged then (if your DMM is acurate and the charging just stopped when you measured them).


----------



## dlong (Jul 14, 2010)

This link (http://www.eneloop.info/products/chargers.html) would imply that it just charges for 16 hours?

BTW, can someone explain the differences between:

Charge Control: -delta V
Charge Control: Peak-Cut-Control
Charge Control: delta V


----------

