Car Batteries, they come to my shed to DIE

[Esteban]

Is my battery charger shit? Its a projecta superstart or something, from repco. I dont remember how much I paid for it...

Background:
Over the last year or so I've had 4 car batteries of different types on standby for the all-too-often flat-battery scenario... and for cars sitting around the place that are, erm, permanantly parked. Since I shelved my car projects for the entire year of 2006, i decided to put some of the batteries on charge so they wouldnt die.

Now the scheme I had, was the four batteries sitting on a large wooden cable drum, up off the concrete, out of the damp, close to the breezy back-door, nearby the battery charger and the washing machine. I checked the water in all of them about once a month, and only needed to top them occasionally with distilled water. I do my clothes washing every weekend, so I regularly swapped the charger to another battery at this opportunity.

However, life got rather stressful during sep/oct/nov and I wasnt changing it as regularly. Yes, this was directly proportional to my clothes washing efforts ... forwards, backwards, inside-out forwards... you get the drift.

So i went to use the battery sitting on the charger yesterday. I estimate the battery had been on there probably 3 weeks, during which I hadnt topped up the water. The charger had boiled it dry.

So is my battery charger shit, or is it my own stupid fault. Would a decent charger voltage and current regulate the charge so this wouldnt happen? If so, can anyone recommend a better battery charger? I really liked the low maintenance aspect of my setup, just disliked the battery death that ensued...

Perhaps the batteries are to blame? Granted a car rarely runs for three weeks straight with 13.8V sitting across it... Am I missing something fundamental?

TIA

[ProjectSleeper]

Sounds like you need to get a charger that has a "float" mode or trickle charge when it gets to capacity..

I bought a float charger and I had a Battery on charge for about 2 weeks ( Forgot I put it on charge), and it was fine afterwards... No water used, still running in the car today (18mths later)

[river]

Hi,

Leaving the charger on all the time could be frying your batteries. It should trickle charge the battery once the battery is at capacity, but I wouldn't leave it on for more than a day.

seeyuzz
river

[Esteban]

Yeah, I gathered that my charger lacked a decent regulation circuit. I have an old 12v charger with float, but it only takes a solar input from 0-40v ish so i'd need to buy or build a 240 stepdown... hence why im wondering about a decent charger and where to get it :-)

[CrUZida]

My charger recommends hi-charge for no more than 24hrs, and lo-charge (trickle) for no more than 7 days.

A battery in good condition should easily last 3 months sitting on a shelf while keeping enough charge to start a car.

[Esteban]

What charger is that? 7day trickle would suit me fine, where can I get one?

Battery in good condition hey, well, three of them were century brand, and the largest of those was two years old and had spent only 6 months in the car, never run flat, and always kept charged, it died first.

I can get 400cca $160 SLAs easy, at that price I wont be too unhappy if it only lasts two years light duty i suppose... wont buy century again obviously.

[tooch]

There are some trickle chargers available that are designed to be left plugged in for long periods of time, people use them for boats and motorbikes and stuff.

[CrUZida]

ARLEC 4A from memory.

You can buy this kit from Jaycar to put inside it to regulate the charge.
http://www.jaycar.com.au/productView...Max=&SUBCATID=

[The Witzl]

You want the "Battery Fighter" chargers - these are designed to be left on a battery PERMANENTLY. A lot of chargers out there claim to be float chargers, but they are actually just trickle chargers.

Jaycar links:

http://www.jaycar.com.au/productView...Max=&SUBCATID=

http://www.jaycar.com.au/productView...Max=&SUBCATID=


These chargers have won design/innovation awards, and i have only ever seen ONE returned faulty to us which looked like it had been left in the engine bay and went for a trip to perth....

[Esteban]

Sold ++rep

[Jorrs]

kind of related to this, my battery keeps dying and not having any charge left in it to start the rolla, it ran fine for a week, then suddenly it doesnt hold charge, its a dry cell battery and the alternator is charging fine, i heard i will need to take the battery to a place to get ti charged as it wont charge up like a normal battery anyways yeh.

[Ribfeast]

Sounds like it might have been overcharged, or charged on a voltage that is too high. If I remember correctly, you need to charge them on around 14.1 - 14.7V, and drop down to a lower voltage when charged.
Batteries will also last longer mounted in your boot instead of a hot engine bay.

[river]

Hi,

Batteries will also last longer mounted in your boot instead of a hot engine bay.

And you have factual evidence that supports this assumption?

seeyuzz
river

[deviant]

Sorry to hijack but...

I have got one of those solar powered deelys that plug in to your ciggy lighter to go in my MR2 for when its not being used (4 or 5 days at the most)...should I just leave it in for maybe 12hours once during that time or leave it plugged in all the time? All our pool cars at work have them hard wired in and sometimes sit for aaages and dont seem to suffer any ill effects.

I would look at the instructions for it but there arent any with it

[CrUZida]

Cars that are sitting around have a constant current draw (radio memory, clock, ecu memory, etc), so there shouldn't be an issue with leaving one of those solar trickle chargers in all the time.

But, best bet is to follow the manufacturers recommendations.