Charging AA Batteries

[Paul M]

I'm trying to charge 2 AA NiMH batteries using a standard battery holder and a smart charger. The batteries are new and advertised as ready to go, which they seemed to be. I had them on charge for about 4 hours last night, but the red charging light stayed red, it goes green when the batteriesare charged. If there's no battery attached the red light doesn't show, so I know there is something attached to the charger. Am I being impatient, or is there a loose connection somewhere?
This is in my Ruby, I checked everything worked before I put it together!

 

[PhilP]

You are being impatient...

You also really need to give the new batteries a good discharge / charge cycle a couple of times..

PhilP

 

[maxi-model]

You are being impatient...

You also really need to give the new batteries a good discharge / charge cycle a couple of times..

PhilP

Ooh, that might explain a couple of issues I have experienced recently with sound failing on two new battery "installations" - one a freshly delivered new purpose made battery powered Roundhouse NDM-6, the other a very recent battery conversion of a Bachmann K-27. Both with brand new battery packs. I charged them fully prior to initial use as per the instructions. I noticed that the sound from these loco's sound cards, different types, failed after a relatively short time of running with the battery only having been charged once. The sound operation restored as normal once the batteries had been fully recharged. Both sound card manuals stated that the loss of sound was a symptom of low battery charge. I shall give it time.,,,,,,,and another recharging session. Max

 

[Eaglecliff]

Can I just mention - a few months ago I bought a couple of LED lights from one of our local garden centres. Packs of rechargeable AA batteries were on sale next to them, so, assuming they were appropriate I threw a couple of packs into the shopping basket. It was only after I got home that I discovered that the batteries were 1.2v, not the correct 1.5v. I had always assumed that AA referred to capacity as well as size - not so. The difference in output isn't huge, the cells will charge up to a little over the nominal 1.2v and the lights work but there may be situations where the difference is critical. Moral - never assume anything.

 

[Rhinochugger]

Can I just mention - a few months ago I bought a couple of LED lights from one of our local garden centres. Packs of rechargeable AA batteries were on sale next to them, so, assuming they were appropriate I threw a couple of packs into the shopping basket. It was only after I got home that I discovered that the batteries were 1.2v, not the correct 1.5v. I had always assumed that AA referred to capacity as well as size - not so. The difference in output isn't huge, the cells will charge up to a little over the nominal 1.2v and the lights work but there may be situations where the difference is critical. Moral - never assume anything.

Re-chargeable NiMh are 1.2v

 

[PhilP]

So are the older NiCad's..
Though 'good' batteries of both types will charge to a higher potential, when new.

If you *really* need 1.5V cells, then look for the hybrid Eneloop type. - These are a hybrid chemistry, give a true 1.5V, and low self - discharge.

PhilP

 

[FatherMcD]

Not trying to be contrary, but where are you finding 1.5V Eneloops? Are they UK only? I'd like to get some if they are available in the US. The Panasonic Eneloops that I'm finding are rated at 1.2V. I have found some 1.5V AA Li-Ion by Xtar that require a proprietary charger. The batteries test at 1.52V out of the box, and run my Playmobil engine quite nicely, but I can't report on how they recharge until the backordered charger arrives.

 

[Paul M]

You are being impatient...

You also really need to give the new batteries a good discharge / charge cycle a couple of times..

PhilP

PhilP thanks for the reply, you were right. I put them on charge again this evening, and they were fully charged about 45 minutes later.

 

[Greg Elmassian]

eneloop batteries are 1.2v rated... as with ALL rechargeable batteries, the fully charged voltage, measured with no load, will be over the nominal voltage.

Greg

 

[GAP]

So are the older NiCad's..
Though 'good' batteries of both types will charge to a higher potential, when new.

If you *really* need 1.5V cells, then look for the hybrid Eneloop type. - These are a hybrid chemistry, give a true 1.5V, and low self - discharge.

PhilP

I was told recently by a battery supplier that there are 2 types of Eneloop batteries one has a black case and is made in Japan while the other has a white/light case and is made in China.
The quality and performance levels are different in batteries from the 2 manufacturing places.
I have not heard of the hybrid variety but will have a look for them.

 

[Greg Elmassian]

Yes. the original eneloop and the "eneloop lite"

Battery guide: which battery type to pick | Panasonic eneloop

Jeder verwendet Batterien: Egal ob Sie ein professioneller Fotograf sind, häufig Videospiele spielen oder ein abenteuerlustiger Wanderer sind, der langlebige Batterien für sein Satellitentelefon benötigt. Auch bei ganz einfachen Aktivitäten im Alltag brauchen wir die Leistung von Batterien. Aber...

www.panasonic-eneloop.eu

In fact there are now 3 types of eneloop, original, lite and pro... the link and the site explain

Greg

 

[korm kormsen]

i have a charger (named "ENERGIZER") with slots for four AA batteries.
and had the same problem as you mention. - when trying to load two batteries.
when i insert four batteries it loads just fine.

 

[maxi-model]

I used to have an Energizer branded charger for use with NiMH batteries of the same brand. Energizer is the rebranded name for the old familiar, at least to us in the UK, Eveready range. I possibly even had the same charger as you Korm, Mine, made for both AA & AAA cells, was in the silver and green branding and had a blue LED display. It would tell you time to charge, if you had a dead cell inserted and which slots to use if you were only charging only 2 cells. I gave up on it and their range of NiMH batteries after a short while as the battery life (light duty appliances) was always disappointing and individual cells would become discharged and even "dead" with a seemingly very short life. Little used it ended up at the recycling centre just a few weeks ago when I was having a clear out. I found decent regular alkaline types would be better as they a have proved they would keep their charge for anything up to 10 years, or even more in devices with limited use. I do use a regular "smart" charger for already existing battery powered locos. Possibly why Roundhouse supply regular alkaline AA batteries with their RC live steamers and not NIMH.

With regards to "Eneloop" brand NiMH batteries it would seem their maker's (or is that s') might have some marketing issues. Doing a general search for the brand does not obviously highlight the different "levels" of Eneloop batteries or their suitable applications that you have handily supplied Greg. Nor does there appear to be any mention of the "1.5 v" rating per cell of any part of their range when making a general search and clicking on the bit about voltages. I was recommended the Eneloop product, for various reasons, when I embarked of the process of converting my track powered stock to battery operation recently. However, when speaking to some UK vendors there was some doubt expressed as to the benefits of this brand over others' NiMh offerings in terms of price/performance. None of those expressing doubt lacked access to this product for the purpose of supply. So I will probably end up with "stock"AA NiMh cells powering my fleet. Max

 

[GAP]

Yes. the original eneloop and the "eneloop lite"

Battery guide: which battery type to pick | Panasonic eneloop

Jeder verwendet Batterien: Egal ob Sie ein professioneller Fotograf sind, häufig Videospiele spielen oder ein abenteuerlustiger Wanderer sind, der langlebige Batterien für sein Satellitentelefon benötigt. Auch bei ganz einfachen Aktivitäten im Alltag brauchen wir die Leistung von Batterien. Aber...

www.panasonic-eneloop.eu

In fact there are now 3 types of eneloop, original, lite and pro... the link and the site explain

Greg

I went searching for the hybrid and came across this site that talked about generations up to pro 5, it would be all so confusing for a non technical person.

Complete rewrapped Eneloops list 2024 ~ by ChibiM

Rewrapped eneloops have been a fairly common topic of debate. Some people claim certain batteries to be eneloops. >>>Watch the following LIST >>>

eneloop101.com

Eneloop rechargeable batteries. Tests and more in 2024

Eneloop rechargeable batteries: A collection of different eneloop battery tests performed by different people in different fields against Amazon Basic Rechargeables, BTY, Duracell and many more.

eneloop101.com

Some serious technical reading to boggle the mind.

 

[GAP]

I used to have an Energizer branded charger for use with NiMH batteries of the same brand. Energizer is the rebranded name for the old familiar, at least to us in the UK, Eveready range. I possibly even had the same charger as you Korm, Mine, made for both AA & AAA cells, was in the silver and green branding and had a blue LED display. It would tell you time to charge, if you had a dead cell inserted and which slots to use if you were only charging only 2 cells. I gave up on it and their range of NiMH batteries after a short while as the battery life (light duty appliances) was always disappointing and individual cells would become discharged and even "dead" with a seemingly very short life. Little used it ended up at the recycling centre just a few weeks ago when I was having a clear out. I found decent regular alkaline types would be better as they a have proved they would keep their charge for anything up to 10 years, or even more in devices with limited use. I do use a regular "smart" charger for already existing battery powered locos. Possibly why Roundhouse supply regular alkaline AA batteries with their RC live steamers and not NIMH.

With regards to "Eneloop" brand NiMH batteries it would seem their maker's (or is that s') might have some marketing issues. Doing a general search for the brand does not obviously highlight the different "levels" of Eneloop batteries or their suitable applications that you have handily supplied Greg. Nor does there appear to be any mention of the "1.5 v" rating per cell of any part of their range when making a general search and clicking on the bit about voltages. I was recommended the Eneloop product, for various reasons, when I embarked of the process of converting my track powered stock to battery operation recently. Add in when speaking to some UK vendors there was some doubt expressed as to the benefits of this brand over others' NiMh offerings in terms of price/performance. None of those expressing doubt lacked access to this product as a point of supply. So I will probably end up with "stock"AA NiMh cells powering my fleet. Max

I bought SWMBO a set of 8 Eneloops for her digital camera (small Panasonic) and every time I turn it on I get "Please replace these Batteries" message and that is only after I take some pictures for the forum one day and try to take pictures the next day.
We are forever recharging them admittedly they came from China, so my experience backs up what the battery supplier told me.

 

[JimmyB]

I bought SWMBO a set of 8 Eneloops for her digital camera (small Panasonic) and every time I turn it on I get "Please replace these Batteries" message and that is only after I take some pictures for the forum one day and try to take pictures the next day.
We are forever recharging them admittedly they came from China, so my experience backs up what the battery supplier told me.

If your other halfs camera takes normal AAs 8 = 12 volts (nominal) whereas for NiMH 8 = 9.6 volts (nominal) so hardly surprising.

 

[GAP]

If your other halfs camera takes normal AAs 8 = 12 volts (nominal) whereas for NiMH 8 = 9.6 volts (nominal) so hardly surprising.

That's a point might put some alkalines in and see how it goes

 

[Greg Elmassian]

If the "small" Panasonic can accept rechargeables in AA normally the manual would indicate it. The nominal voltage difference is so great I surprised it runs even on freshly charged batts... of course after a full charge the voltage can be as high as 1.41 per cell (which goes back to 1.2 quickly).

does it really use 8 AA at a time? (how can it be small? )

Greg

 

[GAP]

If the "small" Panasonic can accept rechargeables in AA normally the manual would indicate it. The nominal voltage difference is so great I surprised it runs even on freshly charged batts... of course after a full charge the voltage can be as high as 1.41 per cell (which goes back to 1.2 quickly).

does it really use 8 AA at a time? (how can it be small? )

Greg

I caused a bit of confusion sorry; the camera takes only 2 AAs (3V v 2.4V a difference of 0.6V) but I bought a set of 8 so she can have spares.
They work reasonably well when fresh but if the camera is turned off and left overnight, then the replace batteries start.
The Low Self Discharge claim is what I have an issue with, because freshly charged batteries left in a battery pouch for a day or so will trigger the replace battery message.
I have AA LSD batteries for my train transmitters, not Eneloop, that last for months in storage and they are from China as well.
This experience has made me wary of Eneloops.

 

[Greg Elmassian]

Ahh... what would be interesting is testing the battery voltage about a minute after the full charge, and then under load... let them sit overnight, and repeat both measurements.

Open circuit voltage does not tell you a lot.

Regular alkaline batteries hole 1.5 volts a fair time and then drop... nickel metal hydrides can taper off a bit more... I would guess the camera is very sensitive to voltage. Also, have you ever actually checked the amp-hours of the batteries you bought? if not a name brand, funny stuff has happened.

Greg