MH-204F & bad batteries

[ps56k]

I have two MH-204F chargers for my handful of various kinds of AA's. Mix of Eneloops, Duracells, ROV Hybrids, Nexcell, etc - All has been well for many years, until recently.
I've noticed that a couple of my Duracell brand cells were not holding up in our weather radio... Now I'm concerned that 1 set of charging bays on one 204F is doing something bad.

The batteries indicate they are charged, green led, and a DVM shows the voltage at 1.35v but they don't work when put into a 1W light for testing, or act funny when attempting a "recondition" after a full charge & rest.

What gives ?

I may have to get a 900 or 9000 charger with the LCD screen to see what's really going on with these cells.

 

[VidPro]

The batteries indicate they are charged, green led, and a DVM shows the voltage at 1.35v but they don't work when put into a 1W light for testing, or act funny when attempting a "recondition" after a full charge & rest.

.

when i read this, it triggers the thought:
did you put a LOAD on the battery when you tested its voltage.
been there done that, horribly high resistance battery will show normal voltage then tank as soon as you try and draw a load off of it.

a light bulb, a 10ohm resister, something like that added in parelel with your meter will show you much and much info beyond the "voltage".

{=====]

|--{~}--|
|-meter -|

|{====]|
|--{~}--|
|-meter -|


hmm, to test your charger, use the DMM in its ammeter (10A current) mode , and make the last connection with the meter.

charger connect point |)--meter---{=====](| charger connect .

then you can also check for AC current and voltage , to see how "dirty" the DC power is .

 

[ps56k]

a load - yeah - that's why I tested them in my RC-N3 flashlight... and BOTH cells appeared bad, which seemed odd. I'm keeping my eye on those 2 charging positions in the MH-204F and will see if any other cells turn up bad.

My concern is/was that the 204F charger was somehow damaging the cells, or it was just some fluke that 2 long time working cells went bad after charging - at the same time.

So, I just ordered the 900 charger from Amazon, so we can see what my cells look like. Unfortunately, I tossed the "bad" cells, so we'll never really know, but going forward, at least now I'll have something to tell me more info.

 

[VidPro]

the MH9000 is "better" than the LC900 IMO

had you dropped the cells? really hard drop kinda drop.

 

[Turbo DV8]

I am not clear on why you suspect a specific pair of charging channels. Did you always charge those two cells in those two bays all these years, and another identical two cells in the other bays, and they are both still peachy?:thinking: