Surprising result from cheap batteries

[Mr Happy]

I have some cheap Chinese NiMH batteries that I got from Harbor Freight for less than $4/4, the ones tested in this post. After I finished testing them, I charged them up and put them aside.

Just recently I decided to examine them and see how they were doing. They had been sitting on the shelf for months, maybe nearly a year.

To my surprise, they all were still over 1.2 V, and still had enough charge to manage a few hundred mAh when discharged on the C9000. One of them managed over 400 mAh. That's pretty amazing for such cheap batteries, and means they could probably be used in low drain devices like clocks or TV remotes.

Unfortunately Harbor Freight don't sell them any more; they have been replaced with "better" ones at $8.99/4. That's no longer a bargain when I can get Hybriloops at $9.99/4. Pity.

In contrast the Energizer 2500 mAh cells in my bad battery hall of fame are both reading 0.9 V. I'm wondering if they will go lower, but I think that is where they have bottomed out.

 

[325addict]

Are those 2500mAh Energizer so bad indeed? I replaced them regularly in some Sound Devices recorders, because I didn't trust them anymore. I always put in the very best Varta 2700mAh cells, these ones are really good, the first one has to fail on me yet....
After recharging the Energizers coming from these recorders, they seemed to have a very high internal resistance and a very, very high self-discharge.

Can you give me some details on HOW they are bad? In what disciplines? This could be interesting to feed back to Sound Devices... You suggest they better use Eneloops??


Timmo.

 

[Mr Happy]

Are those 2500mAh Energizer so bad indeed? I replaced them regularly in some Sound Devices recorders, because I didn't trust them anymore. I always put in the very best Varta 2700mAh cells, these ones are really good, the first one has to fail on me yet....
After recharging the Energizers coming from these recorders, they seemed to have a very high internal resistance and a very, very high self-discharge.

Can you give me some details on HOW they are bad? In what disciplines? This could be interesting to feed back to Sound Devices... You suggest they better use Eneloops??

If you do a Google or CPF search for the Energizer 2500 mAh you will find many references. In short, they tend to develop a very high self discharge rate so that they may go from fully charged to empty in a matter of days.