Calling the Battery Experts!

[easysurfer]

I went ahead and recharged a couple of 9 V batteries. Didn't think much about that as have done so many times in the past.

However, when taking them out of the charger, noticed one of the batteries had a bulge . Can't and not going to use that battery. Must have been overcharged.

Made me think, is bulging battery a sign of a bad battery or bad charger? The other battery was fine and I'm charging another one now to see what happens.

[NW-Bound]

Bad charger or bad battery?

You have to monitor the voltage during charging to know.

[easysurfer]

The charger supposedly is smart enough to not overcharge, but it isn't a fancy one with readouts. Just plug in, red indicator is charging, green means done.

I've recharged before using that charger but this is the first time I got a fat bat .

[HI Bill]

Could be either one. But many batteries today are made poorly, and they tend to have insufficient insulation inside. That said, overcharging would definitely do that.

FWIW, some of the best rechargeables are Panasonic Eneloop batteries. They hold their charge for a couple of years, and don't heat up much during discharge. And I've never had one leak, despite owning more than three dozen! I use them in underwater strobes, high-power camera flashes, remote controls, flashlights, soap dispensers, scales, etc....

Whatever you do, don't trust the copper top.

[easysurfer]

Eneloop are my go to batteries. Wish they made a 9V size.

I've had other chargers that go to hot and one used to melt the label off of Radio Shack rechargeable AA/AAA batteries. This was before chargers became somewhat "smarter".

[NW-Bound]

If the battery is old, one of the cells probably has gone bad, and the charger ends up overcharging the whole thing.

Charger termination is tricky.

See: https://batteryuniversity.com/learn/..._metal_hydride

[easysurfer]

The battery that was bulging was warm when removing. It was sitting idle for about a year unused. Also, not sure if any relationship, but that time I charged 2 batteries where I usually just charge one at a time.

The newer battery (idle for a few years, but never been opened from wrapper) just finished charging. Not warm at all an no bulge.

I don't use 9v batteries too much. But now, I'm thinking about getting a charger (to add to my collection ) that has monitoring and refreshing capability of 9 volts. Like the more popular AAA/AA chargers.

[Jerry1]

Based on your description of your charger, I would give some thought to upgrading the charger to a better model. Something that gives you some information on the health of the battery. Like this:

https://www.amazon.com/gp/product/B0...VHREJU7H&psc=1

[easysurfer]

I just ordered a new battery charger from Amazon .

I re-tested the 9 volt battery that I just recharged, and it isn't holding a charge. Perhaps I left too long unopened and never used. So, out of three 9 volt rechargeables which I recharged tonight, 1 recharged properly, 1 got over charged and bulged and 1 doesn't keep a charge.

The charger I ordered is an Opus brand (same one I have as my gamer for AA/AAA recharging). I like how the batteries lay flat on the charger instead of the usual battery terminals.

https://www.amazon.com/dp/B019DHRCTW

We shall see if the charger can refresh that battery that didn't hold a charge. I'm a bit doubtful, but only one way to find out .

Oh ... I'm considering the charger a gift to myself .

[Jerry1]

Looks like a good choice. In looking for one to give for an example, I was surprised that chargers that include 9v batteries were hard to find, especially ones that have information displays. Looks like you found a good one. Interested to see how it works for you.

[easysurfer]

Quote:

Originally Posted by Jerry1 Looks like a good choice. In looking for one to give for an example, I was surprised that chargers that include 9v batteries were hard to find, especially ones that have information displays. Looks like you found a good one. Interested to see how it works for you.

I'm sure there must be more if I look harder, but so far the only ones I've seen with information displays for 9v batteries are the one you suggested and the one I ordered.

I've try to avoid using 9v batteries when I can. Even bought some things and paid a bit more to use a different battery size as connecting and disconnecting those battery terminals to a stubborn clips should be considered a form on cruel and unusual punishment .

[mountainsoft]

Quote:

Originally Posted by easysurfer Eneloop are my go to batteries. Wish they made a 9V size.

Yep, Eneloop's are my choice too. I use them in everything including remote controls, clocks, indoor/outdoor thermometers, etc. The only thing they don't work in is my Panasonic phones, which apparently don't know how to charge the eneloop's properly.

I wish Eneloop made a 9V size too, but I only use 9V's in our smoke detectors and the metal detector in my wood shop. So, I just buy off the shelf batteries, usually Duracell.

I also wish Eneloop made C and D cell rechargeable batteries. Yeah, there are adapter sleeves that let you use the AA size batteries, but you don't get the long run times of the C or D cells for things like emergency lights or emergency radios. However, it seems fewer devices use C or D anymore. I replaced my old emergency radio with one that has a rechargeable lithium battery bank built-in. I can even use that to recharge our cell phones if needed.

[easysurfer]

Quote:

Originally Posted by mountainsoft Yep, Eneloop's are my choice too. I use them in everything including remote controls, clocks, indoor/outdoor thermometers, etc. The only thing they don't work in is my Panasonic phones, which apparently don't know how to charge the eneloop's properly. I wish Eneloop made a 9V size too, but I only use 9V's in our smoke detectors and the metal detector in my wood shop. So, I just buy off the shelf batteries, usually Duracell. I also wish Eneloop made C and D cell rechargeable batteries. Yeah, there are adapter sleeves that let you use the AA size batteries, but you don't get the long run times of the C or D cells for things like emergency lights or emergency radios. However, it seems fewer devices use C or D anymore. I replaced my old emergency radio with one that has a rechargeable lithium battery bank built-in. I can even use that to recharge our cell phones if needed.

My theory is 9V aren't popular so no desire to make 9V sized Eneloops. I use 9V batteries for two garage door openers and a battery tester that using a 9V battery to put a load during the testing. Also, a couple of not commonly used electronics testing instruments. I used to have smoke detector that used 9V but that got changed to used AAs.

Speaking of adapter sleeves, I've seen some D sized ones can use up to 3 AAA batteries connected in parallel for more capacity. Could be an option if you have a lot of AAs around. But don't know which is more time consuming to use D batteries or all those AA batteries. Interesting, nonetheless.

https://www.amazon.com/Whizzotech-Pa...gateway&sr=8-5

[Jerry1]

Regarding 9v batteries. I know this is about rechargeable batteries, but as has been mentioned, not a lot of good options for 9v rechargeables. I only use one 9v since the smoke detectors went to the non replaceable type so I bought an expensive lithium 9v. This is my point, it didn’t fit! Don’t buy this battery unless your equipment has a little extra room. For some reason, they decided to square off the edges so it is not shaped like most other 9v’s and didn’t fit in my equipment (a thermometer I bought at Costco to take our temperature when ill).

https://www.target.com/p/energizer-u...E&gclsrc=aw.ds

Interesting, when I went to grab the link to show in this thread, it looks like they changed the shape. I may go look at it in the store to see. I can’t stand alkaline batteries. I don’t think they make any that don’t leak. That was my original purpose for going to rechargeables.

Edit to add - The picture of the battery bugged me so much that I went to Target and looked at the actual product. It’s still squared off. Wonder why their picture is not of the actual product.

[SumDay]

I just had my car battery change and it was "bulging" and cranking slowly. He told me batteries expand (bulge) when they get too hot and/or old. Sort of like me.

I had never heard that before. He said hot garages are a likely culprit.

[easysurfer]

Quote:

Originally Posted by Jerry1 Regarding 9v batteries. I know this is about rechargeable batteries, but as has been mentioned, not a lot of good options for 9v rechargeables. I only use one 9v since the smoke detectors went to the non replaceable type so I bought an expensive lithium 9v. This is my point, it didn’t fit! Don’t buy this battery unless your equipment has a little extra room. For some reason, they decided to square off the edges so it is not shaped like most other 9v’s and didn’t fit in my equipment (a thermometer I bought at Costco to take our temperature when ill). https://www.target.com/p/energizer-u...E&gclsrc=aw.ds Interesting, when I went to grab the link to show in this thread, it looks like they changed the shape. I may go look at it in the store to see. I can’t stand alkaline batteries. I don’t think they make any that don’t leak. That was my original purpose for going to rechargeables.

Have you considered a USB rechargeable 9V?

Something similar to this one:

https://www.amazon.com/TalentCell-Li...%2C147&sr=8-18

But perhaps not that one as some folks complain of the size not fitting too.

I have a digital fever thermometer that takes AA sized alkalines and requires the 1.5 volts. Does not work with 1.2 NiMH batteries. I like to use rechargeables and avoid alkalines when possible. So, I bought some lithium usb rechargeable AAs for the thermometer which work great. Long lasting shelf-life before recharge needed, no leaking, no separate charger needed, 1.5 volts.

[Lakewood90712]

Just food for thought. with the exception of cellphones, any battery charging I do is outdoors on the back patio. Have experienced a few overheat situations both long ago and recently, recharging battery's.

[easysurfer]

Looking at the package wrapping of the 9V battery I tried recharging but battery didn't keep a charge. Battery is from 2014. Had been sitting in the wrapping all this time. I have two more batteries in unopened wrapping (was a stock up deal). Will see when I get my charger if that can breath new life to these batteries.

[Lakewood90712]

Quote:

Originally Posted by easysurfer Looking at the package wrapping of the 9V battery I tried recharging but battery didn't keep a charge. Battery is from 2014. Had been sitting in the wrapping all this time. I have two more batteries in unopened wrapping (was a stock up deal). Will see when I get my charger if that can breath new life to these batteries.

Lithium battery chemistry does have a shelf life. Ni cad cells can sit a long time and still be revived in my experience.

[easysurfer]

Quote:

Originally Posted by Lakewood90712 Lithium battery chemistry does have a shelf life. Ni cad cells can sit a long time and still be revived in my experience.

I may have been talking about too many batteries at the same time. Sorry.

The 9V battery which I recharged but doesn't hold a charge is NiMH. The AA batteries for my digital fever thermometer is lithium.

The 9v battery sat in the unopened packaged for about 5 years until I tried charging last night.

As for the AA lithium, seems the shelf-life is just as good if not better than alkalines. As a fever thermometer, that can easily sit in the medicine for over a year until I feel feverish. Not once has the batteries been depleted from sitting around too long.