How to safely charge the car battery?

[StiMan]

Hi,


i drive a second car on rare occasions, but i dont want to unhook the battery to charge it as it then also drains the battery to the Alarm and Satelite tracking system.

is there a device where i can safely charge the car battery without taking the leads off the car. and then can go to trickle mode.


i.e charge the battery while the wires are still hooked up.


cheers

 

[labman]

I don't quite understand the problem. If the battery goes down when the car sets between times without being driven, you should be able to just connect any charger. I have never heard of disconnecting the battery to charge it.

 

[94MaxGXE]

I have one of these, Battery Companion that even has a pigtail connector so you dont have to bother with clamping it on the battery. Got it at Meijer on sale for about $20.

 

[Bob Woods]

I use one of these to keep the batteries on my RV charged. No power cord needed.
http://www.batterymart.com/battery.mv?p=ACC-04021

 

[txmatt]

With most any charger you can charge the battery with the battery still connected to the car's electrical system. The battery will soak up surges and ripple from the charger.

As a couple folks have mentioned, some sort of float/trickle charger is the way to go. You just leave it on all the time. Some of the automatic battery chargers have multiple charging stages and will go into a trickle/maintenance mode once the battery is charged. The dedicated trickle chargers are nice for their small size and many come with simple plug-in connectors. Check the electrolyte level in the battery occasionally in case you have some evaporate off.

Another good thing about the trickle charger is that automotive batteries hate being deep discharged. They're designed to delivery large currents for short periods of time and then be topped off. Some will die after only a few discharges. It's also not good to let batteries sit in a discharged or partially charged state for any length of time. So it's better to keep a battery trickle-charged than to let it sit for a few months and then charge it back up.

Matt

 

[DavoNF]

Bob,

Does that Battery Saver gizmo feed power back through the ciggie lighter?

Dave

 

[StiMan]

quote:

---

Originally posted by txmatt:
With most any charger you can charge the battery with the battery still connected to the car's electrical system. The battery will soak up surges and ripple from the charger.

---

Matt,

I got a Projecta 2200mA battery charger, the first step it says

A. Remove battery from Car.

....


I don't want to fry the cars CPU.

Does the Battery Saver Plus

work off Solar power or off a powerpoint?

this looks perfect if it runs off a powerpoint.
cheers

 

[StiMan]

i found what i am after... its a BMW product...

BMW Battery Maintainer
$69.00
This is a must for your car if you park it for extended periods! The Advanced Battery Charging System is a 1.25 Amp battery charger designed to fully charge and maintain a battery at a proper storage voltage without the damaging effects caused by trickle chargers. The new BTP micro-chip technology applies the correct peak charge, then automatically maintains the battery at the perfect float voltage which virtually eliminates battery destroying sulfation! Temperature compensation ensures optimal charge voltage even in extreme weather conditions. Powder coated aluminum chassis. Spark Proof! Reverse polarity protection ensures safety. Built in 72 hour timer will protect a marginal battery from over charging.
Size: 4.88 x 3.25 x 2.88" Input Power: 115VAC @ 60Hz Weight: 2.7 lbs.

Part Number 82 11 0 026 663

Price $69.00 plus S/H

 

[theguru]

I use a Projecta 1600ma automatic charger. Simply charges it up and maintains the float level. Using 2 of them right now. I don't disconnect anything. I would be a little concerned about anything that wasn't automatic staying on for too long. Also most Solar power units are poorly regulated.

Whats the timer on the BMW unit for? Is it fully automatic? I'm reasonably sure the Projecta unit just won't charge if the battery is faulty.

 

[txmatt]

There's a bunch of these things around. Do some web searches for Battery Tender, BatteryMinder, etc. These are microprocessor controlled chargers and not simple trickle chargers.

The manufacturers will sometimes say to remove the battery to cover their arse. That way if their device malfunctions and damages something they're less liable. In practice, I haven't seen a charger mess up vehicle electronics in the 20 years I've played with 'em.

If you're looking at a charger (solar or otherwise) that connects to the cigarette lighter or power point, make sure that is a constant power source even with the ignition off. If that power point goes off when you turn off the ignition, you can't use it for charging unless you want to leave the ignition on all the time.

Matt

 

[Speed racer]

FYI:
A gel cell battery must be re-charged very slowly; and never directly jump start a car supplied with a gel-cell . But you may use jumper cables from another another car's battery to charge it up. But take off the cables when you try to start the G.C. car.
You don't want hydrogen bubble forming in the gel where they can't escape.
Source: westcoastbatteries.com and my Miata owners manual.

 

[Bob Woods]

Bob,
Does that Battery Saver gizmo feed power back through the ciggie lighter? Dave

Mine does, and if you read the data on the site listed you will see it does too. bob

 

[theguru]

Stiman,
Is the price on the BMW unit $69.95US, The Projecta unit is $45 to 65 Aus, but KMART handle it and occasionally you can get it on discount (15% off).

 

[StiMan]

quote:

---

Originally posted by theguru:
Stiman,
Is the price on the BMW unit $69.95US, The Projecta unit is $45 to 65 Aus, but KMART handle it and occasionally you can get it on discount (15% off).

---

hey guru... the BMW unit is $69 USD

I got a Projecta 2200 for around $25 AUD from Big-W (same as Kmart) on special. I'm not sure its the same unit as yours (EXCEPT YOURS IS THE 1600mA version), coz on my unit it specifically tells me to REMOVE THE BATTERY FROM THE CAR.

I'll type the next bit in bold.....

the reason why i don't trust my Projecta charger to charge the battery whilst the batttery is still connected to the car is, the other day i was charging the battery... i left it overnite... when i woke up my whole house did not have power... the reason was that something triggered off the Mains Safety Switch (this normally occurs when there is some electrical fault e.g putting hair dryer in water)... which i assume was caused prob by something to do with me charging the battery.

[ November 12, 2003, 10:45 AM: Message edited by: StiMan ]

 

[theguru]

Stiman,

Not sure abt the 2200ma version as the projecta website is being updated. I use the 1600ma as it is fully auto and can be left on indefinately. The low amperage means it will also not boil the battery. I have several higher powered units upwards of 10amps but the danger is overcharging. OK for quick charge, generally off the car, but not long term.

The 1600ma is designed so that the unit can actually be mounted in say a boat, tractor etc and you just connect the power and leads as needed.

A sfar as an electricl fault, yes that can happen from a unit, but cars themselves are not immune from this on their own. I know someone whose alternator burnt out his whole wiring loom. Very expensive.