Alfalfameister

I remember one time a person asked if a car battery charger can be used as a power supply to power the hobby charger. This was immediately knocked down because the car battery chargers "didn't put out clean power" and other arguments like that.

Well, now for the opposite:

Can one use a good power supply (20 amp) to charge a [real] car battery? There's also an unused 80 amp Lambda power supply in the warehouse that I might bring into service.

Thanks for any replies!

P.S. I ain't doing anything until INFORMED and CERTAIN answers are given (conjectures not allowed); I don't want to blow anything up!

JNorton

My Feedback: (2)

Sure but the voltage of the power supply has to be above 13.4 volt to charge. 13.8 to 14.3 is ideal. The battery will take more current the more discharged it is, conversly it will draw very little when almost charged. I would use the 20 amp PS.
John

Alfalfameister

That's good to know...

But then, isn't the regular car battery charger just 12 volts? I guess I'll have to whip out the voltmeter.

What I did notice on a regular battery charger is that it has an amp meter (ammeter?). The longer I charged the battery, the lower the current draw, as you have mentioned.

I will see if the lambda power supply has a volt-control (variac or something).

Is the power supply better for charging than a regular car battery charger, considering it puts out "cleaner" power?

Thanks!!! This forum is really useful!

Alfred

JNorton

My Feedback: (2)

Nope more like 13.8 to 14.4 volts.
Might have a voltage control pot on the circuit board. Check using the model number on the Internet to find out. Sometimes I just use the model number alone on "Google".

No to the battery it doesn't matter and it's a lot cheaper using pulsating DC.

John

Alfalfameister

Not if you have a regulated power supply lying around!

Thanks for all the responses, John!

Alfred
--Manila, Philippines

JNorton

My Feedback: (2)

Your welcome.

Geistware

My Feedback: (16)

I use a bench PS to charge my trailer battery. When my car is connected to the trailer, it will charge both batteries. I set the voltage to 14.5 volts for overnight charge, or 13.8 volts for an extended charge. I usually keep it connected until the current drops below 100ma