Battery charging question for kid's toy Jeep

[smackoj]

I'm trying to get a Jeep play car battery charged without using a wall wart. It has two dc motors on the rear wheels and those are powered by a 12v lead acid motorcycle battery. It says the initial charge current is 2.70 amps. It came with a small wall wart charger that takes multiple hours to add just a couple volts to the batt. The wall wart provided with the Jeep is obviously not up to the task.

Can I use a full size car battery charger set on 'slow chg' to charge this size of battery? Obviously I don't want to blow the top of the Jeep battery.

Thanks for any help you tech fellas offer.

smacko  jack

[sluckey]

I think so. I'd definitely try it.

Something to consider... I modified one of those jeeps many years ago so that I could use a riding lawnmower battery. I can't recall exactly what I did, but I think all I did was use some big cable ties to secure the battery and maybe put some ring lugs on the battery wires. The kid got a lot more windshield time between charges and I used my standard car battery charger.

[kagliostro]

Charge your battery max at 1/10 current of his nominal

that will prevent damage on the battery

use a car battery charger with current regulation

K

[smackoj]

I'll give the Schumaker a try. It's new fangled and has built in safety features which runs a diagnostic prior to sending the juice so I'm pretty confident it won't slam the motorcycle battery at start up. Thanks guys for your counsel.

jack d     

[PRR]

It *does* take "multiple hours" to charge lead-acid without damage.

Your car battery charges quicker, but its service life is shameful. (Also we rarely run a car starter battery way-down, the way the kid drives the Jeep until it won't budge.)

Fast discharge is also bad.

Ideally you use the 1/10th AH rule. In other words, it should take 10+ hours to get a full charge, and 10- hours to use it up.

Since the discharge rate is fixed, what you need is a battery so big that it runs near 10 hours, delivering about 1/10th of its rated AH. I'll guess the Jeep averages 10 Amps, so you need a 100AH battery. The batt in my plow-truck is 56AH, so you need twice that. Aside from cost, the weight is near 100 pounds. This may *double* the cruising weight, hurting performance, and incidentally raising the Jeep's demand to more like 12A-15A.

And the motor cooling is probably selected for short run-time of the original battery. Zoom for 30 minutes, charge for 4 hours. Extend that 30 minutes to several hours, the motor may melt.

You are finding out why we don't drive lead-acid electric cars.

Magic-Ion batteries are somewhat better, more expensive (especially one at a time), and demand very fussy charging or they get sick and explode.

Gasoline is the answer. I saw a neat 650cc 4-wheel the other day.

[eleventeen]

No pun intended, but that was a power-packed post PRR! Well stated all around.

[smackoj]

.....So, my choices are a messy, high cost space junk batt, an old school batt the size of Miami or a sooped up ATV? I'm gonna have to think on that awhile....or ask the 8-ball CEO decision maker....or consult Madam Tinkerbell's horoscopes....dang Mr P!

I think I'll just watch football and if the 'Fridge' runs for another TD in Chicago, I'll try putting a ducted fan motor and a parachute on it so I can catch my grand daughter!   

or not, just depends I guess