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how charge AA battery 1.5v (DURACELL)

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Alkaline batteries should never be charged. It should never even be attempted, as they could easily explode.

Battery chargers will explode alkaline batteries. Impart this is because the chargers are built for NiCad and charge at a high rate.

I have recharged DuraCell Copper Top batteries, or other high end batteries, with good results under certain conditions.
>I can not get energy back into low cost batteries. Use Copper Top
>You can not let the battery totally discharge. If you take out 10% of the power, you can put it back in, many times.
>Keep the charge current very low.
>Limit the charging voltage. This is critical.

A friend built a test rig that, every day, discharged a D cell copper top to 90%, then put back in 20% of its rating over the next 23 hours. This repeated for 8 months until the power went out during a discharge and totally discharged the battery and ended the experiment. By using the top 10% of the battery he got 240 cycles.

Before that I was using 9V copper tops in wireless microphones. Each week we used 25% of the battery. In four weeks the microphones would fail. The charge cycle put 50% of the rated current into the battery over 7 days. I got 52 weeks of service from these batteries. Every year I replaced the batteries and they only held 50% of the energy as a new battery. I understand they are still using these charges 15 years later. (The charger used pulse charge mode, low current, and very accurate voltage limiting)
 
There also exist truly recharchable alkaline cells, the RAM cells. https://en.wikipedia.org/wiki/Rechargeable_alkaline_battery

Yeah, I remember when we went through this. The joke is:

If they are discharged by less than 25%, they can be recharged for hundreds of cycles to about 1.42V.

If they are discharged by less than 50%, they can be almost-fully recharged for a few dozen cycles, to about 1.32V.

The punch line is, they work great as long as you don't try to use them.... in other words, discharge them and they lose their rechargeable capacity. One of the major battery makers tried to peddle these back in the 90's and it was a complete flop: the basic problem is, if you want them to retain any usability, you can only discharge them a slight percentage of capacity. That means you have a large battery pack taking up size and weight and it has very little usable mA-hr capacity.

I couldn't believe it when they tried to sell these things. I haven't seen them around for a long time.
 
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I remember those dumb alkaline "RAM" cells. Low capacity, lousy recharge capability, absurdly high internal resistance - kept getting recommendations to use them from people who couldn't be bothered to check the specs.
 
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