AA Battery Tester and Battery questions.

[mike_s]

So about a year ago I bought some AA 2300mAh NiMH batteries and a charger for camera and strobe.

I've been having some issues with batteries not lasting long and I think I've identified the "suspected" bad battery that was causing the problem.

However, I'd like to be able to test batteries batteries before hitting the water due to having some batteries "die" during a dive. (which I think was charged with the suspect bad battery).

So has anyone bought any "good" battery testers? and have reccomendations?

I went to Radioshack and bought one of thiers, but it's pretty wimpy and only shows you "green" for good and "red" for bad. Unfortunately camera batteries need more life to them than flashlight, etc batteries and even batteries that the camera says are "low charge" show up as green/good in the RadioShack tester.


I asked ScubaLuke about this and he found this tester and has ordered one for "testing/evaluation". It's nice feature is that it "load tests" the batteries.
http://www.thomas-distributing.com/zts-mini-mbt-battery-tester.htm

I was just wondering what other folks might be doing to test their batteries?

Thanks for any information.

-Mike.

 

[Logiconor]

Hey, why not use a multimeter?
itll give you VERY accurate measurements, and YOU can decide whats good and bad yourself

 

[Larry C]

Electronic load testers are really nice, and $28 is a good price. Another way to do it would be.
1. Fully charge the battery and test it with a voltmeter (the red/green test) it should be within 10% of the specified voltage.
2. Put it in your strobe or camera and turn it on for about 5 minutes.
3. Retest the voltage. If it has dropped substantially, your batteries won't hold charge under a load and it's time for new ones.

I believe Thomas dist. also has a battery renewer. It sucks all the current out of the battery and recharges it from scratch, for batteries that have taken on a charge memory from recharging too soon. Might work, might not.

 

[Puffer Fish]

So about a year ago I bought some AA 2300mAh NiMH batteries and a charger for camera and strobe.

I've been having some issues with batteries not lasting long and I think I've identified the "suspected" bad battery that was causing the problem.

However, I'd like to be able to test batteries batteries before hitting the water due to having some batteries "die" during a dive. (which I think was charged with the suspect bad battery).

So has anyone bought any "good" battery testers? and have reccomendations?

I went to Radioshack and bought one of thiers, but it's pretty wimpy and only shows you "green" for good and "red" for bad. Unfortunately camera batteries need more life to them than flashlight, etc batteries and even batteries that the camera says are "low charge" show up as green/good in the RadioShack tester.


I asked ScubaLuke about this and he found this tester and has ordered one for "testing/evaluation". It's nice feature is that it "load tests" the batteries.
http://www.thomas-distributing.com/zts-mini-mbt-battery-tester.htm

I was just wondering what other folks might be doing to test their batteries?

Thanks for any information.

-Mike.

Thomas is a great place to buy from and they have a great charger/tester selection. You should keep in mind the following:

1. Dropping a NiMH's can damage it.

2. They only last so long, so don't be silly on an important trip.

3. If you are worried, get an individual cell charger.

4. Before going on a trip, do a dump and recharge. A good charger will have the ability to do this.

5. Get a load tester if you really want to know if it is good.

I am using the 2,700's that Thomas sells right now - great batteries. They also sell camera specialty batteries, but you have to go elsewhere for the chargers usually.

 

[mike_s]

2. They only last so long, so don't be silly on an important trip.

well they are only about a year old (if that) and don't have but maybe 20 dives spread out over 16 different AA's (my camera uses 2 and strobe uses 4).

I would think they shouldn't have failed this quick. any of them.

 

[spoolin01]

This late post may never be noticed, but I think the replies missed the mark. In my relatively brief experience (maybe 120 AAs), I notice about a 10% rate of bad AA NiMH batteries (Kodak, Powerex, Nexcell, Sanyo, Panasonic, generic imports, you name it), but as noted they are not expensive so it's easy to avoid the 'weakest link' penalty for a whole set by identifying the bad ones and replacing them. The simplest way I've found is to use an intelligent charger (negative delta-V controlled, not timer) that has fully independent channels (Maha, Ansmann, there are others). When charging, the bad cell will take an unusually long or short time to charge. You can't go by voltage because that's not usually the problem - capacity is the problem. There are chargers that will dicharge and/or quantitate the capacity of battery packs, but I've not seen one that's good for doing this with AAs. Also be aware that the move to chargers with quick charging times (apparently a consumer demand), means the battery life is shortened. It's not uncommon for chargers to pour 500-1000 milliamps per hour into an AA cell, which is approaching 50% per hour charge rate. That's extreme. Find a charger with 100-300 mA charge rate and your batteries should last longer. Also - never use non-intelligent chargers.

 

[Charlie99]

A very simple technique for finding the bad or weak AA cell is to run your camera, strobe, or whatever until it shuts down due to low battery voltage. Then measure the voltage of each AA cell with a multimeter. If one cell's voltage is dramatically lower than the others, that's the weak cell.

No fancy test gear needed; just a cheapo multimeter from Radio Shack or Home Depot. This method also has the advantage that the your are testing the battery with the exact type of load it sees in real usage.

 

[mike_s]

This late post may never be noticed, but I think the replies missed the mark. In my relatively brief experience (maybe 120 AAs), I notice about a 10% rate of bad AA NiMH batteries (Kodak, Powerex, Nexcell, Sanyo, Panasonic, generic imports, you name it), but as noted they are not expensive so it's easy to avoid the 'weakest link' penalty for a whole set by identifying the bad ones and replacing them. The simplest way I've found is to use an intelligent charger (negative delta-V controlled, not timer) that has fully independent channels (Maha, Ansmann, there are others). When charging, the bad cell will take an unusually long or short time to charge. You can't go by voltage because that's not usually the problem - capacity is the problem. There are chargers that will dicharge and/or quantitate the capacity of battery packs, but I've not seen one that's good for doing this with AAs. Also be aware that the move to chargers with quick charging times (apparently a consumer demand), means the battery life is shortened. It's not uncommon for chargers to pour 500-1000 milliamps per hour into an AA cell, which is approaching 50% per hour charge rate. That's extreme. Find a charger with 100-300 mA charge rate and your batteries should last longer. Also - never use non-intelligent chargers.

I'm thinking about getting that Maha charger that charges cells independently.

I still haven't gotten the tester yet. Santa didn't bring it, so I'm most likely going to order it now.

 

[spoolin01]

I've been using the CH401FS for several years and love it. I wish they'd make an 8 or 10 channel version (and a lighter weight transformer...) Along with charging the cells independently, it has a low power setting that charges at I think 100 mA rate. The voltage measuring idea is also a great diagnostic - I take a VO meter when I travel and it's a great battery management tool (like when I forget which ones are charged...)

 

[azcaddman]

I have the new maha mhc-9000 charger, check it out on thomas-distributing .. it only does 4 at a time, but has a nice 'break-in' mode, does full charge/discharge/charge cycle in addition to all the 'ususal' ones, you can set the charge amperage rate, and it displays all the details, for each battery separatly.