[gtp]

Hi,

I bought a cheapo "Titanium PowPower" 9.6V, 160mAh battery for portable amp use. I also bought the 2x9V smart fast charger, which seems to work great (tested on my other 8.4V rechargeables). However, there are some wierd issues with the batteries, I'll describe the symptoms and possibly somebody has some ideas:

I fully charge the battery and it measures 10.5-11 volts or something high like that. I plug it into the amp and it works for a few minutes, then starts to die (I hear clipping, the LED dims). I pull it out, measure the voltage, and it is ~6 volts. Here is the wierd part, if I wait half an hour, and measure the voltage again, it is back up to 10.5-11 volts! Again I try it in the amp, and it works for a few minutes before dying.

I guess the maxim "you get what you pay for" applies and I should have bought some Mahas in the first place. The thing is that all these 9.6V rechargeables seem kind of "cheesy" and cheapo looking, so it is hard to tell which are legit brands and which are not.

Anyhow, it is an interesting puzzle that someone might have an idea about.

Thanks,
George

 

[labrat]

Deleted.

 

[tangent]

First, the phenomenon of the battery voltage going back up when you remove the load is normal.

When the battery voltage drops precipitously under load, it means it doesn't have a full charge. If you cannot ever achieve a full charge, the charger is broken, or the battery is dead.

The small cells of 9V batteries mean they do not respond to fast charging as well as larger cells. (Remember, there are 8 little cells inside a 9.6V battery!) I think fast chargers are just a marketing gimmick, and you bought it. I have yet to see solid engineering behind fast chargers for 9Vs.

 

[gtp]

Quote:

Originally Posted by tangent First, the phenomenon of the battery voltage going back up when you remove the load is normal. When the battery voltage drops precipitously under load, it means it doesn't have a full charge. If you cannot ever achieve a full charge, the charger is broken, or the battery is dead. The small cells of 9V batteries mean they do not respond to fast charging as well as larger cells. (Remember, there are 8 little cells inside a 9.6V battery!) I think fast chargers are just a marketing gimmick, and you bought it. I have yet to see solid engineering behind fast chargers for 9Vs.

So according to the charger manual, the charger does fast charge for two hours, then trickle charge after that. I could try charging overnight to give the trickle part a chance to fully charge the battery??? I'll give it a shot, and if they don't work after that, then I'll chuck the batteries.

I know the charger works because I have some Rayovac 8.4 volt batteries that measure 10.5 volts after 2 hours of "quick" charge and last a good week in my Cmoy.

George

 

[SiBurning]

Don't judge a rechargable battery until you've cycled it a few times. If it gets better, keep cycling it until it gets used to being used. Do it Quick so you can return them if they don't revive.

Are these nicd or nimh? Is the charger made for that type?

 

[gtp]

These are NiMH that I bought with the matching charger.

I tried charging overnight (fast for 2 hours, then trickle for the rest of the night). When I popped them into my amp, great, they worked fine...then 20 minutes later died.

It seems that the batteries are just cheap crap and are defective. It's too late to return them, oh, well.

My twin 8.4V Rayovacs will have to do for now.

Thanks,
George