hpcbmw wrote:
Does anyone know if a C-tek charger will desulfate and charge an almost dead RV or car battery? I'm under the impressions that you want alot of charge at first, then taper off to a low charge as it tops off. The C-teks look pretty small - can the put out that much charge? Maybe size doesn't matter....
Right now I'm tending towards the Stanley 40amp BC4009 at Lowes for $100.00 - it's close by and I've got a $10.00 credit there.
Thanks
The Multi unit from Ctek has a maximum amp output of 4.3A. You will be waiting a long time, if ever, of bringing your batteries back to a full charge.
What you need to do is a charge-an equalization charge-final charge. Depending on what size battery you have, you want to charge, initially at a modest rate-5% of capacity would be a good number. What I do is leave a charger on the battery overnight at less than this rate, maybe 3A, at start.
Next, you want to give the battery an equalization which stirs the electrolyte and knocks off some sulfation. Check with the mfg. for this rate but it will get the battery visibly bubbling. I do this with my shop charger set to the 40 amp rate and it really is too high of a voltage for most batteries but I keep my eye on the process. It is usually about a one or two hour process. I observe for water level and fill if necessary.
After the equalization, I set the charge at less than 2A and leave it again to charge overnight. Depending on how the battery is going to be used, I may then test each cell with a hydrometer. If any cell is below par, the battery gets replaced. If all cells are even and show close to full charge, it goes back into service.
FWIW, last week I replaced the battery in my F-250. It was 10 yrs., 1 month old. It would still spin the engine on cold mornings but I didn't trust it at extreme cold temps.
