onboard trickle charger
 

hey all i know it's early to start thinkin of winter but i was thinking to make sure the batteries are always charged what if i installed a small trickle charger and wired it into the block heater plug so when the block heater is pluged in the batteries are charging also. any suggestions? o and where do you guys suggest wireing this thing into the solonid or into the battery terminals themselves? thanks again tim

Problematic idea...
Why?

A trickle charger delivers only a small amount of current. You won't be able to recharge an already weak battery because the battery will not accept the charge as it does under warm conditions.

To avoid that condition you will need a charger being able to deliver a bigger charge current if needed.
Do not forget that trickle chargers are intended for use with stored batteries and never taken off the power supply.
The next problem is that the charging voltage will be to low while under trickle charge to avoid gassing of th cells and water loss.
You need a charger being able to recharge the battery and to cut the charge voltage down to trickle charge after charging your battery. Have in mind that even a bigger charger with a proper controlled charging rate will need several hours to recharge your battery, if you insist on a non damaged battery.
A trickle charger will not deliver the current which is needed to complete the charging.

Maybe you will read the following threads to understand the battery itself:
https://www.dieselbombers.com/genera...uble-time.html

had the same problems, solved it with this unit:
https://www.dieselbombers.com/shade-...y-charger.html

I don't know how true this is as military vehicles do have trickle chargers on most trucks they have at reserves. I know that you can buy them all day long for your trucks online. At least I can from a supplier out in OH.:tu:

i was just talkin something to make sure they are always charged like wire it into the block heater so when the heater is plugged in so is the charger. just ian idea.

That's a good idea, if done properly.
Just make sure ground of the truck is connected really good with the ground on mains voltage. Mains voltage can kill you with ease if a failure occurs (cable chafing or abrasion).
A protection device can and will save you and your dependents if a failure occurs.
How many ampere hours are you going to plan to trickle charge?

probally only like 10 amp just one of the cheap ones ya can find at pepboys or napa

Wow... 10 amp is not a trickle charger.

what ya sugest? amp wise? 2 maybe just somethin to keep the batteries fom gettin really cold and useless.

any one? saw a battery maintainer for like boats and stuff any ideas? just tryin to keep them batteries charged good and keep em warm

I was using one of these when I still used my block heater:
Cheap Best Battery Charger Reviews » Blog Archive » Solar SOL-1002 1.5 Amp Underhood 12V Automatic Battery Charger
I had it come on at the same time as the block heater. No, it won't charge a dead or weak battery, but it sure did give them that little extra. It's 1.5 Amps and automatic, $40 from Amazon.