My car is sometimes laid up for long periods. Can anyone advise the best way to trickle charge the battery in situ to prevent the alarm and self-discharge from causing a flat battery?
Are there any web sites that discuss this topic?
Cheers,
Phil Liverpool, UK
In days of yore, before all of the electronics junk in the car, I would remove the battery and charge it daily for about an hour using a commercial battery charger. The current draw was about 4 amps. I had it set on an applicance timer. Nowadays, you may kill your electronics if you remove the battery.
Al
Available from $20. Yukio YANO
Greetings,
Check out this,
Not sure you have harbor freight stores over there, great place to pick up cheap tools as well.
take care,
markus
I had a good read a week ago in a charger manual. The charge protocol they advise for stored units, is to charge until full,then charge some more at a lower current,and after that to wait until self- discharge drops the voltage to something like
12.2 to 12.4, after which you repeat the cycle. There are some chargers,which do this automatically, and have a temperature sensor at one of the poles,because the whole story about charge/discharge is very temp related. I dont remember the brand, but it is a US one(I think) used a lot in marine environment. Extended trickle charge seems to damage your plates somehow, and can spell disaster(ask my friend,he had to clean his entire boat with soda water to remove the evaporated sulfuric acid,at the end of the winter)
What you need is a charger with a "float charge" setting/switch. This holdes the battery voltage slightly lower than on full charge to stop excessive gassing/boiling. I got one of these chargers from a car parts place for £12 about 10 years ago.
Note read the spec check that the float charge is done at reduced VOLTAGE. Some makers say their charger automatically switches to float charging at the end of a normal charge cycle when what they actually mean is the CURRENT reduces at the end of the charge... which it does anyway on a lead acid battery.
You still need to check the water level every few weeks/months.
holdes
£12Try this one from maplin... Long URL may need repair.
CWatters wrote: ...
Good grief. The battery isn't that old. They're all "no maintenance" units nowadays aren't they?
Phil
That's for little sealed units, not a car battery. Still, it gives me an idea of what the voltage should be - About 13.8 for float charge I think.
Thanks,
Phil
Well even the so called zero maintenance batteries I've used have lost water over long periods of time.
think.
or these...
Chris
That looks useful, and there's lots of technical info as well.
My thanks to all who have contributed to this thread.
Phil
Best in the market.
I use the OptiMate III on my bike. No Sunday biker should be without one.
- Steve
Have something to add? Share your thoughts — no account required.
Ask the community — no account required