Pb/H2SO4 bat'ries.

[mael]

[mael]

[mael]

[mael]

[AlaskaStar]

[SeaMonkey]

The Sodium EDTA method was used occasionally to try and remove accumulated Lead Sulfate from the cells by making it into a water soluble compound (chelate) that could then be flushed out. It worked to some extent as long as the plates hadn't shed too much of their active materials.

The method described by Alaska Star is one that is frequently used, or some variant of it, by battery shops and rejuvenators to restore life to a dead/weak battery. It only works if the Lead Sulphate hasn't aged into it's more permanent crystalline structure by sitting uncharged for more than a year.

Today it has been discovered that electrical desulfating circuits work very well in all forms of Lead Acid battery; from automotive to home power to gell cell to starved electrolyte sealed. The desulfating pulses are able to convert the Lead Sulphate back into active material by a slow process that non-destructively restores battery life - as long as the cell in question hasn't developed a short circuit.

Google or Scroogle "Desulfator" or "Desulfator Circuit" to find the active links with all the history, details and diagrams.

Also there are Forums available for those who are experimenting with the devices to share experiences and ideas.

My experience with rejuvenating Starved Electrolyte sealed cells/batteries has been extremely good, even with cells/batteries that have been sitting unused for several years.

It is a slow process that doesn't consume much electrical power so therefore much patience is required. But, to keep a battery going indefinitely can be very rewarding and cost effective.

[mael]

[mael]

1. clean, adjust H2O as necessary.

2. Preliminary charge - watch for shorts and other anomalies.

3. Bulk charge. - Usually to around betwen 14.5- 15.5V.

4. Bulk charge manually switched to lower current to remain around 14.5 - 14.9V

5. Eq charge at low current for a day or more if the SG indicates further progress is likely.

6. Long float charge. Again, if the SG has shown signs of improving then continue until improvement has practically stopped.

7. Rest. - after rested, test SG & Voltage and check for shorted/shorting cell.

* This may be the end of the charging regime for a lucky few.

8. Load test (in multiples of 65 Watt h/lamps at the moment). Discharge batt to between 10.5 & 11 Volts, Add EDTA, Pulse-charge slowly up to (usually) 14 -14.2 Volts. - This can take a day or much longer.

9. Adjust electrolyte, load test again.

10. Final (hopefully) charge.

This is essentially what I am doing.

* I have noticed little difference between pulse-charging using my 1 - 3 ppsec setup and a carefully monitored & lengthy manual charge. Perhaps others have more obvious success with pulse-charging over other methods than I have?

* I have two surviving pulse-chargers at the moment. One charges a 30,000 mfd cap at about 28V and discharges this into a batt at a rate of 1pps. I can select the pulse duration between 0.5 secs on - 1 sec off, and 1 sec on - 0.5 sec on.

The other is similar, but the caps total about 16,000 mfd, and the Voltage is in the region of 60 - 80 V. (This blew the MOSFETS in short order). It is now effectively attenuated via a sturdy rheostat and other resistance elements as necessary.

* I have noticed more success with the little pulse-charger over an extended time than I have noticed from using the larger one. But it is not so clear at the moment.

[redriderno22]

[redriderno22]

[mael]

[redriderno22]

[mael]

[SeaMonkey]

[mael]