buying a lead acid car battery suitable for running a charger.

[mad-wolfie]

Didn't really know where to raise this (these) question(s), so here goes.

Thinking along the lines of i may need to buy a 12v lead acid car battery so i can take one to race meetings where there is no mains hook-up so i can use it to charge cells, run a lamp, perhaps even a 12v soldering iron etc etc, but also thinking this will not only answer a couple of questions i have, but may be a good idea for a buyers guide, so i;ve added a few extra questions for some brain-storming....

1. if buying a 12v lead acid battery what size/rating do i need to go for & why? bearing in mind most 12v rated RC chargers charge at about up to 6 amps when on a 12v supply.

2. what could i carry the battery around in? I'd need some sort of suitable container - some clubs demand it - what do you suggest.

3. would just buying a cheap / basic car battery be OK or do i need a leisure battery.. after all i'm only running a charger & possibly some basic lighting etc, not starting a canal boat engine or using it in a car.

4. this is more of a general enquiry... where can i buy a suitable battery? - obvious answer is places such as motor spares shops or tyre/battery suppliers to buy one intended for a car, but i'm thinking along the lines of other places such as Maplins or even caravan shops who may sell them along with suppliers such as RS, CPC etc which don't neccesarily have 12v lead acid batteries for cars in mind. Some auto stockists & tyre & battery places simply won't sell you a battery over the counter unless you can prove you have a car & they insist on fitting it.

5. would a motorcycle battery be suitable (bearing in mind they are often used in fire alarms & the like) or would they go flat after a couple of charges.. again i'm thinking along the lines of i've got to carry this to places & a bike battery is a lot smaller & would fit inside an old biscuit tin & such (filled with sand of course).

6. is there a way of doing it on the cheap i.e. buying a salvage one from a scrap yard, specialist supplier or recycling facility etc.

7. would a gel based battery or a sealed one be better than a lead acid battery or an unsealed one... also would i still need a container of some sort as there is no acid to spill.

8. once i have my battery, what maintenance / care do i need to undertake.

[Skiddins]

For starters, you want a Leisure battery not a car battery.
Car batteries are designed to give huge outputs for a short period (starting the car), leisure batteries are designed to give lower output for a longer period of time.

If you're running tyre warmers and a charger for one race day, 85Ah might be enough. If you're just using a charger you could possibly go lower.

A motorcycle battery isn't going to be man enough.

I use a Halfords 110Ah (was £75 but they are now £100! :eek:) which I've had for 4 years and a Numax 85Ah (£55) which is around 2.5 years old and is on it's last legs.

Don't go to a scrappy as the battery will have had a lot of life taken out of it, unless you can find a caravan that is virtually new and is having it's batteries scrapped.

You can order online from a lot of caravaning/marine sites etc.
Make sure you get a decent charger.

Skiddins

[Dave Treacy]

Alternatively get a car battery with a 3 year warranty....used every weekend it will be knackered before the 3 years are up and you get a free replacement...

Keep the receipt!

[mad-wolfie]

Alternatively get a car battery with a 3 year warranty....used every weekend it will be knackered before the 3 years are up and you get a free replacement...

Keep the receipt!

There is that i suppose. Although you could i suppose use a car battery as opposed to a leisure one if you keep charging/discharging on a regular basis. By this you would probably be fine come summer when the peak of racing comes along & the battery gets it's good dose of use & gets recharged on a regular basis, although be it a car battery or a leisure battery you should adopt the same technique & charge it on a slow charger rather than one of those booster chargers.

By this i mean, trickle charge the battery for a while & then discharge the battery on something such as a caravan light - ideal if you want some light in your shed or a bit of extra night-lighting anywhere in the home on the dark nights.. i remember years ago, when i was doing CB radio, i used to run a CB off a car battery & a slow charger (along with an array of 12v car lights obtained from a scrapyard for pennies).. basically charge the battery when needed & regular use of the CB kept the battery in top condition... plus of course it meant all my friends who were using home-base sets or via mains PSU's usually ran into trouble during a power cut, where i kept on going!

I know for motorbike batteries you can get a thing called an Optimate, which basically works like a cycling system that charges & maintains the battery automatically, so if you park your bike up for the winter, this keeps the battery primed while it's standing so come springtime you don't have to put a new battery on the bike.. some people say they are a nuisance & can harm the batteries, but usually this is down to operator error because people don't follow the instructions. I'm not sure if they do such a device for larger batteries, but it may be an investment if they did.

[Wilabidd]

Car Batts are fine, i use a GO sealed car batt 65ah. I run Tyre warmers and two chargers, On fully charged i managed five meetings before charging again