Now about 40 baterries of various size ranging from 17 a/h to 150 a/h litter one wall of my 'workshop.' Unfortunately a lot of them have only been pulsed slightly and then stored as I wanted to sift-out the ones with shorted cells/disintegrated plates so that I would be able to just hook them up to the pulsers methodically without worrying if they were beyond hope.
The ones I rejected are outside. The 40 or-so remaining batts inside range from virtually un-done, to done, but some have been left for a couple of months or more and I've allowed myself to get a bit confused about the condition of the ones I've finished - and would like to sell/give away so they can be doing some good.
Anyway. I finished the pulser I mentioned I was planning. It's pretty powerful and on the highest setting it will be pushing 20 - 30 Amps. I have been testing it on perhaps half its maximum on a fairly large 95a/h starter battery. (Ya gets 'small' 95 a/h batts 'n all ya see). So far I am not disappointed.
The sg was in the red after a preliminary charge, and the electrolyte was low in the cells. The cells are virtually all at the maximum level or perhaps a tad over, and the sg on all but one cell is at or over 1260, and the last is hovering at 1250 - a bit higher perhaps as it settles in the green. That's about three days pulsing.
I used two FK10sm MOSFETS for the final negative output. They are driven by a flasher-circuit going through a relay. The relay's n/o position is wired to ground. The transformer will charge the caps (about 40,000 mFd) to 36 Volts, and I can set the current/pulse count and to a degree I can alter the pulse width. At the moment it is pulsing at about 15 ppS. It'll go up to about 40, and the slowest I can set it apart from DC is about 5 ppS.
So ... That's a largish 95 a/h batt virtually 'done' in three days. I'm hoping to take that batt off and store it so I can begin to sort the batts out into 'done' and not-done. I imagine this will merely mean they are moved from one wall to another via the pulser.
I'm actually quite pleased with this one. I am always worried about the others, but though they might get hot if I push them, none of them have overheated to the point of being dangerous . - The most dangerous situation I can envisage at the moment is if the leads aren't properly secured on the battery terminals and a spark setting a cell off. But (touch wood) I've managed to avoid an explosion despite there having been a few occasions where it might have been possible.
I've taken to using clamps if the clips I use do not grip the terminals tightly. I'm still using old clips I picked-up on a couple of the pulsers and will change them to new ones as I am able.
Of those six batteries I have being done by four pulsers, all but two of the (total of) 36 cells are clearly within the green with the electrolyte at max - level. Three days ago after a preliminary charge none of the cells were in the green and perhaps half were in the red, and a quarter were almost water.
* I'll be happy to post pics of all my family of pulsers. Actually all but one of the five I've got are all lined up on a table all working at the same time doing a total of 6 batts. I've got two pulsers doing two batteries each.
AS got me thinking about pulse-discharging, and I'm ready to have a go at making a pulse-charger/ pulse-discharger this time. I will be using my somewhat primative relay/mosfet/transistor circuits. I imagine I will use a double-pole with n/on + n/off sets of contacts.
I'll probably discharge through a load (like an auto bulb) and charge through caps through the semiconductors. I haven't really thought about it yet, but I would like to make a pulser which alternately charges and discharges.
* I had an idea about using a piezo 'tweeter' as a pick-up to input feedback through a rectified amp which is wired to the terminals. I was wondering if I might be able to resonate the battery and if this would clear the plates of sulphation?
As I imagined it, the plates were all cleared of sulphation and the battery fully charged in 5 minutes - I get these ideas as I try to make myself sleep, y'see.

What has been won by the brave at great cost can be lost cheaply by fools and once gone can rarely be regained and only then at great cost.