12V 60A car battery , maybe dead?

[eklogite]

First, Hello to great forum and great people...

Dear GL,
I have read all the thread about your circuits, batteries and suggestions.
I have a few questions that you may help me.

I have 4 SLA 100AH batteries which are heavily sulphated, cells are also dried.
I opened first battery caps and added distilled water up to cover the cells...
I can see thick 4-5 mm white lead sulphate crystalls on plates using a flashlight.
The batteries accept charge and I charge them with a 10A PWM solar charge controller with a 80W panel made myself.
The battery accepts charge and the actual capacity is ~5AH. Voltage is 13.25- 13.35 at full charged state.

I want to use the charger circuit you posted in page 7.
Since 100AH battery capacity makes a very high current, don't you think the coil L2 may heat up and burn ?
When going to start, should the battery be discharged or partially charged?
I have a 12V 1A switching power supply to use for this propose, is it a good choice?
What resistor do you suggest ??
I have also trouble finding the components here, does 2n3055 transistor preform okay

Thank you very much,
Eklogite

[eklogite]

Hi there,
I have built the circuit in page 7, it is working fine but there is a small problem.
The current that the charger puts on the battery is only 50-60 mAh !
The battery voltage is going up very slowly.
I were unable to find the suitable core and used a 10mm drill bit instead of the ferrite rod core.
I am now charging the 100Ah battery, will post the results after my first cycle.
Power supply is 11.5V 3Ah

Thanks again.
Eklogite

[ViKARLL]

Hi Alex,

I have read this long thread and your detailed replies given with immense patience. 

I have a few questions before I get started to build this interesting circuit. My apologies if I happen to ask a question to which you have already replied in the past.

I have acquired the BU 2508AX transistor, the 470R 5W resister and the cap 220nF 250V. I was stuck with the Ferrite rod since they are no longer available in my country. But I have managed to source out the following;

1) A Ferrite rod removed from an old AM radio - Diameter 8mm and length 80mm (it is sort of oval, not round!)
2) Another Ferrite rod I managed to grind out from a TV Fly-back transformer core - Diameter 14mm and length 20mm.

Which one is better and what changes should I do to the number of turns and the gauge of winding wire?

My batteries are in the range of 6V 90Ah to 12V 65Ah.
 
Thanking you in advance for your kind reply,

Cheers,

ViKARLL

[ViKARLL]

Hi Alex,

Any luck with the information I requested?

Thank you,

ViKARLL

[ourbobby]

To Groundloop,
                       Hello, I know it is possible that you have discontinued replying to this very interesting thread. However, you might chance upon it again. My question is this. what is the maximum voltage the original circuit you proposed with the trifilar coil will raise the 12volt battery to? As I believe that the voltage of 15.5v on another forum has been suggested for a continuous use of the Lead Acid battery by allowing a complete conditioning of the plates, when charging the battery at the higher voltage, thus giving the battery an extensive longer life. Will it be possible to rise to this voltage without boiling the batteries with your charger?

I look forward to you passing by this thread again and replying to my post.

Thank you