Recharging Battery?

If I recharge a battery in my Honda with a trickle charger of 2 amps, is it
possible to charge it while it is on the car, or will this harm the
computer? Secondly, if I remove it, can I insert one of those battery
operated memory savers that plug in the lighter? Finally, where can I
purchase a memory saving device?

Thanks,

Nino

 

I am not sure what you mean when you say you want to trickle
charge it... on the car. The alternator is not designed to
re-charge dead batteries, period. Using it do so reduces the
alternator life. Skim the following for more information:
http://home.earthlink.net/~honda.lioness/id13.html

Why did the battery run down in the first place?

If you have no idea, there may be more than the battery to
check here.

 

What I mean is, I plug in my amp trickle charger into the wall outlet, then
I connect it to the battery while it is still on the vehicle. Usually, I
disconnect the battery from the car, and then I connect the trickle charger
to it. When I do this, I lose all my radio presets and computer codes, etc.

Nino

 

My battery is not at its optimum rate. It's three years old. I can usually
make my batteries last up to 10 years, by cleaning the posts, the case and
finally by recharging it once a year using a 2 amp battery trickle charger.
I did this with my last vehicle and got TEN years out of the battery. I
intend to do the same with my Honda CR-V. However, I'm not sure if it's
safe to recharge it while it's still on the car. Especially wit all the
computer equipment aboard.

 

There may be other reasons, but I personally can't advocate
this because of the following: "If left unattended, []
cheap, unregulated trickle battery chargers can overcharge
your battery because they can "boil off" the electrolyte."
http://www.repairfaq.org/ELE/F_Car_Battery.html Also, it's
hard to control the charging parameters. Lastly, this site
also talks about how the parasitic loads on a car with the
engine off can amount to as high as 20 amps. I don't have
confidence right now that the charging setup you're
proposing would work.

I do see advocated at this site getting a second battery,
connecting it via a cigarette lighter hookup, then removing
the battery you want to charge. This retains the computer
memory, radio settings, etc.

OTOH, I do see you have other experience with this. Getting
ten years out of a battery is nothing to sneeze at.

In short, in your shoes and with the experience you claim,
I'd get a second battery, hook it up via the cigarette
lighter, then charge the other battery off the car as you
describe you've done for years.

Sorry, that's probably not much help.

 

I have used a battery charger to recharge our cars (various makes
including Honda) occasionally over the years. This was done with the
battery connected but with a good regulated charger that reduces the
charging rate as the battery becomes recharged. I have never had any
problems with the car's electrical system or accessories(radio,
etc.)from doing this. I believe this is because while the charger's
output to the battery may vary during the charging process, the battery
itself limits what reaches the electrical system. I also have charged
batteries that were removed from the car. When I did that, I connected
a 12 volt DC source(a 12V DC computer power supply--these have highly
regulated outputs) to the battery cables in order to not lose the car's
computer settings etc. Having said all that, as was suggested to you
earlier, find out why you battery needed to be recharged.

Ken

 

I do this all the time, but you raise an interesting point. If you have a
cheap, unregulated battery charger that overcharges your battery and boils
off the electrolyte, the proper place for it is the trash bin. I got eleven
years out of the original battery in my Jeep, including several times
draining it to nothing by leaving the lights on. (I didn't do that on
purpose.)

You can charge a battery that is still connected to the vehicle, but it is
not a good idea to do so without monitoring the amps gauge on the charger
and what is happening with the battery. Lots of bubbling and excessive heat
are bad. A high charge rate for a long time is also bad.

Earle

 

Ever obnoxiously curious, I groups.googled (using keywords
like {charge battery disconnect car} on this point, and it
seems many people do re-charge with the battery still
connected, but with some trepidation, particularly on newer
cars where the electronics can be fried by sufficiently
irregular voltage or too many amps. Others (with expertise
and what seemed to be reasonable explanations) said they
wouldn't risk it on newer cars, period.

Like you say, there was a lot of chatter about using cheap-o
trickle chargers vs. more sophisticated chargers that taper
off the charging as the battery gets closer to full charge.
People seemed to feel much safer (as far as damaging
anything on the car) with the more sophisticated chargers.
Yet time and again, I'd see posts saying the cheap-o trickle
charger worked fine with the battery still connected.

You better believe I am impressed with you and the OP for
getting 10+ years out of a battery via a separate charger.

 

A 2 amp charger is probably too small to do damage to your electrical
system.
But, beware of the word "probably".
If the voltage with the charger hooked up is less than 17 volts, you are
ok, the car electical system is very tough and will probably
(there's that word again)
withstand up to 20 volts from a 2 amp source with no problem.
Easy check: turn on the headlights, if they are visible your battery will
accept 2 amps with no problem. If they don't, disconnect the battery first.
if your battery is almost dead, figure the charge time required
time = battery amp-hours divided by charger amps times 1.25
example : 35 amp hrs/2amp charger * 1.25 =22 hours for a full charge.
The amp hour rating should be written on the top of the battery
In your specific case a 2 amp charger could be left on for two days
without damaging a healthy battery.
If you do not feel comforable doing this, just leave the battery in and
unhook one cable (the negative one, preferably) and hook the charger to the
battery, when done reconnect the battery- but there goes the radio and
stored trouble codes for the engine .
Even a properly working charging system may need a battery charge in
certain conditions, namely very short trips all the time and a lot of
electrical accesories on -as an example, two miles to work, ac on full
both ways, lights on on the way home.

 

If you want to use a charger often, to maintain a battery fully
charged on a vehicle that doesn't get driven regularly, get a
so-called "smart" charger. They can't overcharge your battery. I
keep one full-time on my Jeep and one on my Honda scooter. Both are
driven only once in a while. Battery Tender Plus 12V.
http://www.batterymart.com/battery.mv?c=battery_tender
http://www.batterytender.com/default.php?cPath=11_2

Dick

 

The critical thing here will be not so much how cheap the charger is as
how well it protects the car system from "events" on the mains power. If
a possum vaporises itself in your neighborhood switching station, does
the spike get through into the car electronics? The expensive chargers
may be better, but I wouldn't want to rely on it. It depends on what the
designer thought adequate and what the cost accountants would permit, so
there is really no telling...

 

Isn't the cigarette lighter accessory dead when the ignition is off? I
wanted to use one of those solar-powered tricke chargers that plug
into the lighter but was told my CR-V wouldn't accomodate a charger
operating through the cigarette lighter.

On Sun, 02 Jul 2006 21:40:13 GMT, "Nino NoSpam"

|If I recharge a battery in my Honda with a trickle charger of 2 amps, is it
|possible to charge it while it is on the car, or will this harm the
|computer? Secondly, if I remove it, can I insert one of those battery
|operated memory savers that plug in the lighter? Finally, where can I
|purchase a memory saving device?
|
|Thanks,
|
|Nino
|
|

 

It's true. Honda configures the lighter/accessory sockets to only work when
the ignition is on or in the Acc position. On my 2000 TL, you could make it
always hot by simply moving one wire to an adjacent unused pin in the
connector at the fuse box. That connected it through an always-hot fuse of
the same rating. Check the wiring diagram for yours, it might be that easy.