Charging an SLA with a car charger?

[joecool85]

Would charging a 5AH SLA be a bad idea using a 1.5amp car charger like this: https://www.batterychargers.com/details.cfm?prodid=SE-1-12S&catid=18 ?

 

[kchriste]

It should work ok. You'll need an inverter to convert the car's 12Vdc to 120Vac for the charger.
This one may be a better choice:
https://www.batterychargers.com/details.cfm?prodid=SE-1562A&catid=18
Only because it states that it Automatically switches from Full Charge to Float-Mode Monitoring where as the other one's AD doesn't say.

 

[joecool85]

I wasn't going to use it in a car to charge the battery, I just meant it is a car battery charger and I wanted to use it for an SLA. Good to know it should work though. Thanks.

 

[joecool85]

Would it be better to use something like this?
https://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=2518

It is a 1amp SLA smart charger. I know it would work well for the 5AH SLA, but would I be able to charge a car battery alright? I know it would be a little slow, but other than that any problems?

 

[RODALCO]

Normally to play it safe you charge at about 10 % of the battery capacity.
Say 5 Ah will gets charged with 500 mA. over a 10 to 12 hour period.
If you charge at 5% of Ah capacity you can leave it on for longer 1 to 2 days without damaging the battery.
You could put a 12 volt 21 watt bulb in series to reduce the charging current a little.

When the battery is nearly full the current is nearly zero amps and hardly any volts drop will be across the lamp, so the automatic on off should hopefully sense the output voltage correctly and start stop charging at the right time.

 

[joecool85]

That doesn't answer my question though...

Basically what it boils down to is that I have a 5AH SLA and a car battery that I want to charge (not at the same time) with the same charger. Should I use a 1.5amp car battery charger, or the amp "smart" charger that I listed?

 

[Tarsil]

That doesn't answer my question though...

Basically what it boils down to is that I have a 5AH SLA and a car battery that I want to charge (not at the same time) with the same charger. Should I use a 1.5amp car battery charger, or the amp "smart" charger that I listed?

I think that the 1.5 A car bat charger is a bit too much for the 5Ah SLA and a very slow charger for the car batery. What's the car's bat Ah? The smart charger is ok for the SLA but eaven slower for the car bat. If It's like 55Ah...charging at 1.8% might take ...80 Hrs.

 

[joecool85]

Not sure of the car's AH. I know its 500 CCA, but that doesn't mean much. It is a type 58 in a 2001 ford zx2.

 

[Tarsil]

I'm not quite sure ..but 500CCA means something like...charging current 5000mA.....that means 50Ah. Usualy the bat's rating is written on it. At least in Europe .

 

[JimB]

I'm not quite sure ..but 500CCA means something like...charging current 5000mA.....that means 50Ah. Usualy the bat's rating is written on it. At least in Europe .

Completely wrong!

CCA = Cold Cranking Amps.

This is the ability to provide a large current for a short period to start an vehicle engine at some cold temperature.

Use google to have a look for a tutorial on lead acid batteries.

JimB

 

[Tarsil]

Completely wrong!

CCA = Cold Cranking Amps.

This is the ability to provide a large current for a short period to start an vehicle engine at some cold temperature.

Use google to have a look for a tutorial on lead acid batteries.

JimB

Damn!...I made wrong guess. Th for pointing that out!

 

[audioguru]

If you need a charger for a car battery (why?) then get a charger that is made to charge a car battery. Not a "trickle-charger" that might be good if you go away for a few years (to jail?).

If you need a charger for a little battery then get a charger that is made for a little battery. Not a big one that will boil the little thing dry.

 

[Tarsil]

Audioguru is wright. U can buy/make both circuits quite cheap and use the same transformer for powering them.

 

[joecool85]

If you need a charger for a car battery (why?) then get a charger that is made to charge a car battery. Not a "trickle-charger" that might be good if you go away for a few years (to jail?).

If you need a charger for a little battery then get a charger that is made for a little battery. Not a big one that will boil the little thing dry.

Its not a trickle charger, its a 1.5 amp smart charger, 3 stages. And the reason I want to charge my car battery is that car batteries don't get properly charged by the alternator. I mean, it works ok, but ok at best. If you want your battery to last long, its a good idea to periodically (two to three times a year) charge your battery with a good charger. This is especially important if you live in a cold enviroment and/or make frequent short trips (less than 30 minute drive).

 

[audioguru]

A car battery lasts as long as 5 or 6 years if you take good care of it. It lasts only 5 or 6 years if you don't take care of it.

 

[joecool85]

A car battery lasts as long as 5 or 6 years if you take good care of it. It lasts only 5 or 6 years if you don't take care of it.

Huh?

A car battery should last between 5-7 years with no maintenance in a properly running car with a good electrical system. If you run a lot of short trips and run in cold weather (both of which I do) then it shortens life span to 4-6 years. By charging it periodically, even with the short trips and what not, it brings life to 5-8 years or so. This is from personal experience and also lots of research. In theory, if you were in a warm climate, drove relatively long distances when you used your car (longer than 30 minutes each trip), never let it sat very long (more than 1 month without running), and had a good electrical system and periodically charged your battery, I would think 8-10 years might be possible.

Charging it before winter (and maybe once in the middle of winter) helps cold starts because alternators frequently only charge batteries to 75% or so (due to varying factors) and batteries work better in the cold when they have a closer to 100% charge. Here in maine we have 4 months where it is frequently below 40F degrees and 1.5 months or so where it isn't uncommon to have a week or so of below 0F.

 

[audioguru]

Modern sealed car batteries die due to overcharging causing a loss of water. Trickle-charging an over charged battery won't do any good.

Break off the sealed cap and put some water in it instead. Or turn down the alternator's voltage so that it doesn't overcharge.

 

[joecool85]

I don't think overcharging is the issue rather than under charging.

 

[Nigel Goodwin]

I don't think overcharging is the issue rather than under charging.

I agree with Audioguru, overcharging is far more damaging than undercharging.

 

[joecool85]

I agree with Audioguru, overcharging is far more damaging than undercharging.

I'm sure that it is, I just don't think my battery is over charging.