Harry Bloomfield wrote:

submitted this idea :
I'm puzzled by your comments. What sort of lead acid charger is not voltage
regulated?

I didn't actually mention it not being voltage controlled. I had in
mind it might have been a very basic simple charger, using basic
voltage sensing to switch a relay when a set voltage was reached across
the battery. I have one such in my workshop, which charges an emergency
starter battery/ min compressor type thing. You plug it into the mains,
it charges until the battery reaches a set voltage then switches the
charge circuit off. It then remains off/ not charging until the next
time the mains supply is cycled. It is rather a neat way to do it and
proving the mains supply is cycled very occasionally, such a battery
will be kept in good condition for decades, with little electrolyte
evaporation.

I think that would only work for trickle charging. If you want to
charge at a decent rate then the battery has to be charged at a somewhat
higher voltage, overlapping what would be the fully charged voltage.

--

Roger Hayter