Using a trickle charger - any rules on this?

On Jun 30, 12:31*am, wrote:
> If you are concerned with 1 amp overcharging the battery then all
> one has to do is plug the charger into an automatic timer set for a
> few hours a day.
>
> I've done this with NIMH batteries and low amperage dumb chargers.
> With this method you can't ruin the batteries and you'll always have a
> spare set of fully charged batteries.

I heard that there might be a small parasitic load from an unpowered
charger. Probably doesn't matter if it's recharged each day.

> Contrary to what many people believe, completely discharging a lead acid
> battery doesn't do much harm. Mostly, *the damage is done when
> recharging it. I think you are looking at something like 3 days to
> charge a fully discharged battery with 1 amp.

Hard recharges do damage batteries, and long slow charge works
reasonably well on dead ones.
However, heavy discharges do damage batteries. They may survive
several deep discharges with no apparent harm,
but each time a car battery is forced below 10 volts, plate damage
occurs in the form of sulfur dendrites(?)
Some are knocked off or dissolve during normal cycling, but not all,
and this takes up active area on the plates.
HTH
Ben

On Jun 24, 2:22*pm, "Steve W." > wrote:
> y_p_w wrote:
> > So here's the deal. *The car is a Honda Civic with a group 51 battery
> > (Kirkland Signature from Costco if that helps). *Every once in a while
> > the battery is heavily drained because a light (map light or headlamp)
> > was left on. *I do find it annoying that there is no headlight-on
> > warning chime or auto-off. *Sometimes it starts and sometimes it needs
> > a jump; a portable jump starter always does the trick. *The car itself
> > is driven maybe a few times a month for short distances along with the
> > occasional long trip.
>
> > So I got a simple Schumacher Electric 1 amp, 12 V trickle charger -
> > the kind with thin wires and light-duty clamps coming out of a wall-
> > wart. *It's labeled as a "manual charger" and the box/directions state
> > that it's suitable for charging motorcycle and other small batteries,
> > or for keeping auto batteries warm. *I wasn't sure if I could justify
> > getting anything more expensive like a higher output charger or maybe
> > even a float charger/maintainer with a charge sensing mechanism.
>
> > So I'm wondering how safe this is with a group 51 battery, which is on
> > the small side for auto batteries? *I realize that it's not likely to
> > fully charge up a depleted battery unless it's on for days at a time.
> > How safe is a 1 amp charge if uncontrolled like a float charger? *I've
> > heard some concerns that it could potentially overcharge - that maybe .
> > 25 amp is about the limit for safe trickle charging. *I've heard other
> > comments that it's effectively a trickle charge that could safely be
> > left on a fully charged car battery for days if not indefinitely.
>
> A manual charger that size won't do much. However if that battery has
> been drawn down that many times it is on borrowed time. I would replace
> the battery, then fix the warning chime. Unless that car was made before
> about 84-85 it has a lights on warning chime. The other option is to
> install a battery buddy. They monitor the draw on the battery and cut
> the power before it gets to low to fail starting the vehicle.
>
> --
> Steve W.- Hide quoted text -
>
> - Show quoted text -

92-95 civics don't have a headlight chime. used to be available from
kmart or walmart or such (i got mine from jc whitney) but you can hook
up any kind of 12 volt chime/buzzer between the "hot when lights are
on" and "hot when ignition is on" terminals on the fuse block.

On Jun 29, 9:13*pm, john > wrote:
> Yeah. At least in the US it's now *required* to have a key chime, not
> an "option".

key chime, or headlight chime? key chime, i got (although it's
intermittent, which is worse than none at all). headlight chime, no.

On Jun 25, 6:04*pm, y_p_w > wrote:
> Really - I got used to the headlamp switching off with the ignition on
> my Subaru. *My wife has also forgotten. *

good old volvo 240, same deal.

>
> Didn't I mention that I always carry one of those portable battery
> jump starters? *I remember once driving the Civic to Lassen Volcanic
> National Park, accidentally leaving the lights on for about an hour at
> the trailhead. *When I got back the starter wouldn't turn, I went to
> the trunk to get the jump starter, and opened the hood to connect it.

with a manual trans, i just try to always park on a hill. saved me a
few times.