Eneloop Charge Time?

Do they usually take 5 hours to charge? I started charging a set at 10AM and it's 2:15 and they still aren't charged! Still flashing green.

I haven't timed mine from being dead but that doesn't sound too far out of line. They take quite a while to charge. Usually I put mine on the charger at night and let them go until morning.

Thanks. The box says 220 minutes for 4 AAs (a little over 3 hours) so I was worried something was going wrong with my charger. Glad to hear this is normal-ish.

My Eneloops always seem to take forever to charge. I just assumed it was because I wasn't using an Eneloop charger and was using my Energizer charger. Guess they're just slow to glow.

Charge time will depend on what sort of charge/amperage you are putting into the batterie/s.
Hobby chargers are great for this kind of stuff as they can charge your batterie/s really quick and to a good capacity.
If you do a search for a 'imax b6 charger' you'll find they go for around $30 and will charge just about anything.

Charge time is dependent upon battery capacity and charge rate.

Time = (Capacity / charge rate)

Generally the most healthy rate for NiMH is 200 mA/hr to 500 mA/hr. And the capacity for most NiMH AA batteries is in the range of 2500-2700 mAh.

You can charge them faster (more mA/hr) but the heat generated at the faster rate is not good for batteries...best to have fan cooling of the batteries if charged at a faster rate!

Wow...good to know that. My MAHA/Powerex C-9000 charger defaults to 1000 mA/hr.

Wilt wrote in post #12442683
Charge time is dependent upon battery capacity and charge rate.

Time = (Capacity / charge rate)

Generally the most healthy rate for NiMH is 200 mA/hr to 500 mA/hr. And the capacity for most NiMH AA batteries is in the range of 2500-2700 mAh.

You can charge them faster (more mA/hr) but the heat generated at the faster rate is not good for batteries...best to have fan cooling of the batteries if charged at a faster rate!

Unfortunately Wilt's information is incorrect. Have a read of the article on battery university, a great resource on batteries.

NiMH cells should be charged at about 0.5C, so a 2000mah cell should be charged at 1000mah. This is the same recommendation that Maha/PowerEx makes. At this speed I find cells don't get particularly hot, but at 1C they can do.

The only exception is if the cells get hot, and a good charger monitor this for you. The C9000 is what I use, along with a C801D.

Thanks for that link, Tim.

tim wrote in post #12443723
Unfortunately Wilt's information is incorrect. Have a read of the article on battery university, a great resource on batteries.

NiMH cells should be charged at about 0.5C, so a 2000mah cell should be charged at 1000mah. This is the same recommendation that Maha/PowerEx makes. At this speed I find cells don't get particularly hot, but at 1C they can do.

The only exception is if the cells get hot, and a good charger monitor this for you. The C9000 is what I use, along with a C801D.

Wait Tim, there is no 'incorrect' to the fact that 200-500 mA/hour is less than the 1000 mA/hour upper rate of charge, is there?!

Now having smarta55ed back, I do note the comment in that linked article, "It is difficult, if not impossible, to slow-charge a NiMH battery. At a C‑rate of 0.1 to 0.3C, the voltage and temperature profiles fail to exhibit defined characteristics to measure the full-charge state accurately and the charger must depend on a timer." And in view of that remark, and in spite of the fact that my charger is not timer based, I would start to use my charger's faster rate now.

Anyway back to the OP's question. I find (using the sanyo charger) that anywhere from 5 to 8 hours for the batteries to fully charged. Nothing wrong with your's!

Yep, I tend to allow em to charge overnight - in the supplied charger. I have multiple sets, so multiple chargers... not too bad. Just have to make sure I put them in the wall the night before.