Odd readings and charging for 17670 cell

[jlomein]

Today the AW protected 17670 cell I bought arrived. When it arrived, I used a DMM to see voltage at 3.90V. I placed it on my Ultrafire WF-139 charger. Everything seemed normal, the light was red and flicked green once per second as usual. 2 hours later the light then turned green and I took the cell off the charger. I waited 30 minutes and tested with the DMM. The cell voltage is still sitting at 3.90V.

I tried the charging process again and it is still at 3.90V. I have since charged two RCR123 cells in the charger, and it worked fine (both tested at 4.15V).

Is there something wrong with my charger? Is there something wrong with the battery? Am I not using my DMM properly?

 

[DM51]

You could narrow down the fault fairly easily.

First, test the DMM on other cells. It won't take long to do that and see if it is working properly. It may need a new battery itself. If it says the new cell reads 3.9v, my guess is this is the problem - AW ships them at 3.8v.

If the WF-139 has recently charged other cells OK, it is probably working fine, but you could test it on other discharged cells (not unprotected ones with this charger) and see what happens. It sounds OK, if the light is working as normal.

If both the DMM and the WF-139 are working fine with other cells, it must mean your new cell is faulty. But my money is on the DMM needing a new battery.

 

[barkingmad]

You could narrow down the fault fairly easily.

First, test the DMM on other cells. It won't take long to do that and see if it is working properly. It may need a new battery itself. If it says the new cell reads 3.9v, my guess is this is the problem - AW ships them at 3.8v.

If the WF-139 has recently charged other cells OK, it is probably working fine, but you could test it on other discharged cells (not unprotected ones with this charger) and see what happens. It sounds OK, if the light is working as normal.

If both the DMM and the WF-139 are working fine with other cells, it must mean your new cell is faulty. But my money is on the DMM needing a new battery.

Thought he had tested the other cells 'after' the 17670 and they showed as 4.15 - so unlikely to be an issue with the DMM battery?

 

[AW]

jlomein,

Try to discharge the 17670 ( in a flashlight ) and charge it up. If it won't take charge, send me a PM.

Regards,
AW

 

[DM51]

Thought he had tested the other cells 'after' the 17670 and they showed as 4.15 - so unlikely to be an issue with the DMM battery?

You are right. Don't know how I missed that.

 

[jlomein]

Ok...so today I stuck the 17670 cell in a Surefire E2E (using Lumens Factory 3.7v EO-E1R bulb). I ran it for 45 minutes straight. I removed it from the flashlight and let it sit for 15 minutes. After that, I used my DMM to test it and it showed 3.57v.

I stuck the cell onto my Ultrafire WF-139 charger. During normal charging, the light will be red and flick green for a millisecond, once every second or so. However this time the lights were different. The light will be red for about 1.5 seconds, and then green for 1.5 seconds, continuously alternating. I left it on the charger like this for 2.5 hours. I took it off, waited 15 minutes and tested. My DMM shows voltage as 3.57v.

After that, I used the charger to charge a RCR123 that tested at 3.98v. The lights acted normally, and when it was finished the RCR123 cell tested at 4.15v.

What does the different light sequence on the charger mean?

 

[AW]

It looks like the cell is not taking charge. I 'll send a replacement.

 

[jlomein]

Thanks AW!