Problem recharging gumstick battery

[chippyricky]

I have a Sony MZ-RH10 recorder, and I'm having difficulties recharging the gumstick NH-14WM rechargeable battery.

First time I bought the MZ-RH10 brand new, the NH-14WM battery which it came with was dead and would not recharge. I would press the stop/charge button on the minidisc player while it was plugged into the wall socket via the adapter (as described in the user's manual) and the screen remained blank with no sign of charging the battery in the chamber. The unit itself could function as long as it was plugged into the wall via the adapter, but once I unplugged the unit from the wall, nothing would happen. I sent everything (unit and battery) back to the place of purchase for a new one.

The second unit arrived about six months ago. Just yesterday, after having many successful previous attempts at recharging the battery via the method described in the user's manual, the battery suddenly refused to recharge. Now the scenario is exactly the same as with the first unit I bought - I press the stop/charge button on the unit and screen on the unit remains blank. The unit still functions if plugged into the wall, but it's as if the unit isn't recognizing that the battery is in the chamber. I have tried taking the battery out overnight and then reattempting to charge, tried cleaning the heads of the battery, etc, and i'm just not getting any response from the unit when trying to recharge the battery.

Any help is appreciated. The fact that this has happened with two different units/batteries makes me feel it isn't just a fluke, but either a malfunction or I am doing something wrong.

[greenmachine]

Have you deep discharged the battery? If the battery doesn't have enough voltage, the charger won't detect it.

[Stuge]

Ni-MH.=

1.) Recharge the when Player indicates it is discharged as soon as possible .

2.)Never Keep empty Ni-MH batteries

[chippyricky]

Have you deep discharged the battery? If the battery doesn't have enough voltage, the charger won't detect it.

a week before it went "dead" the minidisc player had about 1/3 full bar of power.

[Avrin]

Try cleaning battery contacts.

[chris_s]

Try cleaning battery contacts.

Hi folks,

I've a MZ-RH10 with exactly the same problem as chippyricky is reporting - the unit works fine using the power adaptor but the battery is completely dead and won't seem to charge.

Thinking the battery was at fault, I bought a geniune new sony battery but it's made no difference so it's obviously not the battery at fault.

I've tried cleaning the contacts to no avail.

I have, however, noticed the following:-

- when you hit "charge" I get a VERY brief flash of 'charging' then it goes blank and doesn't charge when using the mains power adaptor

- plug it into USB of my computer (to try and charge) I got "charging" for about 5 seconds - the battery icon indicates it's filling up, then the battery indicator shows full but then flashes on and off. Take it off USB and the unit works for about 3 seconds then completely dies.

Anyone got any more ideas? (very frustrating!)

Chris.

[chippyricky]

Chris,

This same "charge" flash happened to me with my first battery. I don't even get the "charge" any more with the second (dead) battery.

I am discouraged to hear that a brand new battery didn't get you anywhere either...i was hoping that I had initially been sent a faulty battery or just accidentally overused the second one, but given your experiences, i am beginning to think it might be the battery contacts on the inside of the md player itself.

Hi folks,

- when you hit "charge" I get a VERY brief flash of 'charging' then it goes blank and doesn't charge when using the mains power adaptor

Chris.

[pwscott]

Chris,

This same "charge" flash happened to me with my first battery. I don't even get the "charge" any more with the second (dead) battery.

I am discouraged to hear that a brand new battery didn't get you anywhere either...i was hoping that I had initially been sent a faulty battery or just accidentally overused the second one, but given your experiences, i am beginning to think it might be the battery contacts on the inside of the md player itself.

So my MZ-RH1 arrived today and I very carefully put the battery in just like they instruct, label up etc. Got same exact symptoms you describe! I waited for charging to start, replugged, even looked into battery compartment with super bright light to see the contacts. Damn! Just when I was on the phone with OneCall I saw a diagram on the underside of the recorder showing the non-square end of the battery oriented the other way. I fliped the battery and it charges and is working great. Seems to me label up is right if the recorder is inverted when doing so. I've been a gadget guy a long, long time and have multiple FCC licenses etc- I would SWEAR that the instructions say to put it in the other way. Don't know if that's what your situation may be but thought I'd fess up and pass along.

[igy4life]

what could be the problem? i dont understand I am facing the same problem with my mz-rh10, and recently bought a new battery from aswell thinking it would work, but nothing gives? has anyone resolved this problem?

[igy4life]

what could be the problem? i dont understand I am facing the same problem with my mz-rh10, and recently bought a new battery from aswell thinking it would work, but nothing gives? has anyone resolved this problem?

oh i have fixed it now, just had to add a lil piece of foil, turns out the contacts were the problem after all. hope this helps whoever develops this issue in the future or now.

[chris_s]

oh i have fixed it now, just had to add a lil piece of foil, turns out the contacts were the problem after all. hope this helps whoever develops this issue in the future or now.

Really? Can you give some more details of what where and how you sorted it with tinfoil?

Cheers

Chris.

[igy4life]

Really? Can you give some more details of what where and how you sorted it with tinfoil?

Cheers

Chris.

erm well, i got a pieace on tinfoil then at rolled up and compacted a pieace till it was very dense and about the same height as the little bobble on the positive side, and slightly more width just to make it easier to put it in. The tricky bit is putting it on the the little bobble and closing the battery patch, but with some trials errors you should be able to do it. Anything that conducts electricity would work well, copper wire would work better but there was none available to me, but that basically how u do it.

Again like i said before just try out different shapes and sizes to find which one work the best.

Good luck

Ignatious

[romateo]

I had the same problem. Try pressing the stop/charge button on the minidisc player (while it is plugged into the wall socket) but REMOVE the disc before.

Please let me know if it works.

[jaradthescot]

I am having this exact same problem. I haven't used the MD player in months so I assume it is a case of being completely decharged. I tried the foil method but it didn't help any. Any assistance would be greatly appreciated. Thanks

[sfbp]

Another thing I found - I received what was probably a mostly discharged battery - was that there was green copper compound that was preventing the contact. If you have that, the solution is easy.

Get some alcohol or isopropanol and clean it off all the charging contacts on battery and recorder. That's one reason batteries don't charge... high resistance from decomposition fluids/compounds.

[Strungup]

When a Battery is Completely discharged , no partially , but reaches a voltage level that the chemicals inside no longer recognize as stable ( There can actually be a small residual voltage measured on a meter) but at that "Dead " point a chemical reaction occur inside the battery at the Cathode end , and it begins to crystalize . At that point the battery is ruined , and needs to be recycled , trying to recharge it can actually be unsafe .

in the case of a 1.2 volt NHMD , a residual voltage , of 0.4-.0.3 volts would be unsafe , the chemicals need more than that to keep compound separation .

" Quotation from Green Batteries Battery articles "

The other common cause of damage to NiCd and NiMH batteries is leaving them in a device like a flashlight left "ON" after the battery has run down. Electronic devices normally switch themselves off once the battery is discharged. But other devices like flashlights, cassette players, and many toys, will continue to put a small load (drain) on a battery even after the battery is run down. Eventually (after a few weeks) this drain on a discharged battery will cause the polarity of the battery to reverse (the plus end actually becomes minus and vice versa). Once this happens the battery will not take a charge again. Battery makers recommend that rechargeable batteries be removed from any devices that will not be used for several weeks or longer.

The big difference between voltage depletion, the so called "memory effect" and damage caused by overcharging or improper storage, is that reduced capacity due to overcharging is not reversible.

Edited October 25, 2008 by Guitarfxr

[jaradthescot]

damn.... in that case is there anywhere you'd recommend for me to get a new battery?

[sfbp]

damn.... in that case is there anywhere you'd recommend for me to get a new battery?

Here... these are the same ones I bought

Good luck.

[jaradthescot]

Here... these are the same ones I bought

Good luck.

Thanks, both of you.

[se55y]

When a Battery is Completely discharged , no partially , but reaches a voltage level that the chemicals inside no longer recognize as stable ( There can actually be a small residual voltage measured on a meter) but at that "Dead " point a chemical reaction occur inside the battery at the Cathode end , and it begins to crystalize . At that point the battery is ruined , and needs to be recycled , trying to recharge it can actually be unsafe .

in the case of a 1.2 volt NHMD , a residual voltage , of 0.4-.0.3 volts would be unsafe , the chemicals need more than that to keep compound separation .

" Quotation from Green Batteries Battery articles "

The other common cause of damage to NiCd and NiMH batteries is leaving them in a device like a flashlight left "ON" after the battery has run down. Electronic devices normally switch themselves off once the battery is discharged. But other devices like flashlights, cassette players, and many toys, will continue to put a small load (drain) on a battery even after the battery is run down. Eventually (after a few weeks) this drain on a discharged battery will cause the polarity of the battery to reverse (the plus end actually becomes minus and vice versa). Once this happens the battery will not take a charge again. Battery makers recommend that rechargeable batteries be removed from any devices that will not be used for several weeks or longer.

The big difference between voltage depletion, the so called "memory effect" and damage caused by overcharging or improper storage, is that reduced capacity due to overcharging is not reversible.

I have to say that this quotation shed no light on problem discussed. Yes, reversing is possible in batteries BUT we have NO battery in case of 1,2V NiMH ones like NH-14WM(A). It's a CELL, and even shorting it lead to complete discharge but not to reversing.

The same thing (dead NH-14WM(A)) happended to me recently. I got my Net-MD recorder from Japan and stick refused to charge.

I did some wiring to try charge it with Smart Power Bank from GP and got flashing LED. It means battery is DEAD or alike.

So apparently it's not a fault of recorder (dirty terminals or smth likes).

[larrymd09]

Hello all! I own a MZ-R900 that has been mine for about 3 years. I started having trouble recharging my battery about a year ago. Thinking that the trouble might have been the battery, I purchased a new one from a battery store and still found the same problem. After reading some of the resolves from this forum, I finally corrected or began recharging after adding a small piece of foil to the top of the battery compartment. Cleaning with alcohol did not correct the problem.

Any comments are welcome

[sfbp]

New from battery store may actually be OLD from battery store as these are getting rare. Certainly had that trouble with a new one I purchased from store here. You might do better on the web (look at the link in my post in this thread).

However the general strategy is to run them down as much as possible and then recharge. Better recharging with a charger. Mine is (on recommendation from many members here) a GP charger which I bought with 2 gumsticks.

Scratching the contact with steel wool or a very sharp object such as an exacto knife may help. Be careful though!

Hope this helps.