Battery Charger not charging

[losh1971]

There are some trick chargers out there now the Projecta and Ctek are both great bits of kit. I've had two Projecta ones but I blew them up by using a small generator that surged when it run out of fuel. Replaced it with a Repco 7 stage one but I think the Projecta one was better.

 

[1985VK]

A modern sealed lead acid calcium batteries with thin textured plates wont respond well to a DC welder in the same way an old style thick lead plate open top flooded battery might.

I'd say if you try it, do it in a vented fume cupboard and be friends with a good PPE supplier and have a medic nearby Seriously, having just one mishap and in the process getting sulfuric acid in your eyes wont be any fun at all. Such is pain, suffering and loss of good vision would hardly be worth the possibe savings by not buying a battery for a few more years (if you actually get such a benefit)...

After all, sulpation is a chemical reaction that occurs with the lead plate and acid and actually consumes the lead in the process. Hard sulfation isn't simply reversible

I HAD to try this. In my case it worked unbelievably well on a junk silver calcium battery with only a few volts on it. I would say if you try it do it on a battery with caps you can take off because the "maintenance free" hard plastic cover is really F hard to get off. Started off with around 30A till it got warm, let it cool down and repeat... and repeat and repeat. The amps on the battery came up and the internal resistance went down. I was impressed. The battery holds charge. Maybe it was a fluke.

 

[Skylarking]

I HAD to try this. In my case it worked unbelievably well on a junk silver calcium battery with only a few volts on it. I would say if you try it do it on a battery with caps you can take off because the "maintenance free" hard plastic cover is really F hard to get off. Started off with around 30A till it got warm, let it cool down and repeat... and repeat and repeat. The amps on the battery came up and the internal resistance went down. I was impressed. The battery holds charge. Maybe it was a fluke.

Maybe not a fluke as such but still a little risky, the question is how risky… and really, for the sake of saving $300 on a new battery, do you want to risk getting a Darwin award

 

[1985VK]

Maybe not a fluke as such but still a little risky, the question is how risky… and really, for the sake of saving $300 on a new battery, do you want to risk getting a Darwin award

I did it out of curiosity. In my case there was a bit of bubbling and that was it. Any battery gas could freely escape and there was plenty of ventilation where i did it outside. I regularly checked it with a multimeter and digital load tester that showed the amps and resistance. I also used a non contact laser thermometer to to regularly check the temps on the sides and top to see if it was warming evenly with no hot or cold spots.

Initially the battery tester would say "recharge - retest". I kept charging and resting the battery. I read online calcium batteries need a higher voltage to charge properly. On one of the last charge cycles i cranked the DC welder up so it was pushing out 90 A. It really woke up the battery and improved the amperage. It was interesting but pretty uneventful really.

 

[Skylarking]

Yeah, if I had a safe space that could cope with a mishap I’d also do it out of curiosity

I’ve used a 12v battery charger to spark across the terminals of a Ni-MH battery to bring it back from the dead so they can be charged again. Doing so vaporises the internal “dendrites“ that short the cells but over time the dendrites simply grow back and kill the batteries ability to accept a charge… Risky yes but the risks are smaller due to the battery sizes involved. Thus precautions are easier to take.

Big car batteries on the other hand contain a lot of acid and having such forcefully and fully expelled from the battery wouldn’t be fun in my garage… so I don’t recommend it

Glad it worked for you and it would be interesting to hear how long the battery can provide good service in a car. Maybe a few more years?

Me, I’d have preferred that the tops of batteries can be unscrewed so the internal lead plates can be removed and repaired. A clean, resolder and repack isn’t rocket science and doing such is within most peoples ability… knowing how much current and heat a battery can take before a mishap may occur isn’t the sort of thing most people know. And a trial and error learning process can lead to serious injury unless precautions are taken. For the average Joe out there, who may want to try a battery “welder restore” in his crowded garage, it ain’t a great idea (is all I’m sayin)