teejay Posted June 17, 2011 Posted June 17, 2011 Anyone any experience with deep cycle batteries? I'm after one which is about 80ah and is suitable to take camping, will only be used a few times a year. I'm also trying to hunt down a lead that goes from the battery to provide a cigarette lighter style socket so I can plug in a device that has a cigarette lighter plug on it.
pcstru Posted June 17, 2011 Posted June 17, 2011 I bought one from Halfords 4 years ago for solar power system to my shed (just to run some lights and some odd low power circuits). Seems to be still doing the job OK but would be a big heavy thing to cart round camping. You can get cigarette lighter sockets from Maplins (or other electronics suppliers). You should (must!) run a fuse in-line. 1
maniac Posted June 17, 2011 Posted June 17, 2011 The problem with any battery offering that sort of capacity is it's going to be heavy. I've used one of the 'leisure batteries' from halfrauds (I don't recommend buying one from there thou, as they are very expensive) and used to run a little 12v fridge off it when I went camping - it would run for several days from one of them. They are designed to be deep cycle batteries, infact any battery described as a 'leisure battery' would probably do the trick for you, they're the ones people have in caravans to power the lighting etc. You can charge them up using a normal car battery charger. As for the cable, I made one up myself which I use in my garage for powering my 12v tyre inflator from a powerpack, didn't cost me anything as I already had the bits knocking around. Mike. 1
teejay Posted June 17, 2011 Author Posted June 17, 2011 Yes, I'm aware they are heavy, but it's either lug one around or not go camping as I need to use a CPAP machine to sleep at night. They do some LION batteries for them, but they're £300 and only last a night, whereas an 80ah deep cycle will last 4-5 nights without charge. I'll have a look in Maplins/CPC for the bits to make a lead. There seem to be different types of Deep Cycle battery, any recommendations on type/make?
pcstru Posted June 17, 2011 Posted June 17, 2011 Depends how much you want to spend and how long you want it to last. They tend to be expensive compared to car batteries anyway so if cost is an issue you will be restricted on lifespan and warranty. Get a sealed, gel type if you intend lugging it about. They will still likely be stuffed if you drop them on concrete but you won't be covered in acid. If you have a marina or boat supply near you, it would be worth your while talking to them. There are some golf cart supply batteries which are effectively deep cycle - don't know if they would meet the 80Ah spec, but they tend to be quite compact (might be worth considering a couple of them simply from the handling POV) Just to say, 80Ah is quite a lot of energy and batteries can get rid of that quite fast which can be nasty. Do take care with them :-). 1
maniac Posted June 17, 2011 Posted June 17, 2011 Depends how much you want to spend and how long you want it to last. They tend to be expensive compared to car batteries anyway so if cost is an issue you will be restricted on lifespan and warranty. Get a sealed, gel type if you intend lugging it about. They will still likely be stuffed if you drop them on concrete but you won't be covered in acid. If you have a marina or boat supply near you, it would be worth your while talking to them. There are some golf cart supply batteries which are effectively deep cycle - don't know if they would meet the 80Ah spec, but they tend to be quite compact (might be worth considering a couple of them simply from the handling POV) Just to say, 80Ah is quite a lot of energy and batteries can get rid of that quite fast which can be nasty. Do take care with them :-). Any deep cycle battery will be a Gel type or AGM - collectively called VRLA (Valve regulated lead acid.) A wet cell bettery can only be discharged down to approximately 50% of it's capacity before it starts to have problems, where as a proper deep cycle battery will be able to be discraged down to approximately 80% with no detrimental effects on re-charging. Beware thou, not all VRLA batteries are deep cycle, it's important to make sure the battery is specified as deep cycle if you intend to discharge it a lot, or the life of the battery will be short. As for recommending one to you, can't really help a lot there to be honest. I only know what I do because many years ago I had some training on all this stuff from some nice people at Bosch because of the job I was doing at the time. 1
Sirbendy Posted June 20, 2011 Posted June 20, 2011 On my little solar home system I use car batteries. Yes, I know they're not ideal, but they're a tenner apeice from the scrapyard..and cigarette lighter sockets? Ooh, lots, and lots... Inverters, I have 2..one 80w jobbie (£5, homebase) and one 180w jobbie (ex-PC UPS). Cheap parts to replace.. 1
maniac Posted June 20, 2011 Posted June 20, 2011 On my little solar home system I use car batteries. Yes, I know they're not ideal, but they're a tenner apeice from the scrapyard..and cigarette lighter sockets? Ooh, lots, and lots... Inverters, I have 2..one 80w jobbie (£5, homebase) and one 180w jobbie (ex-PC UPS). Cheap parts to replace.. Normal car batteries will be fine, as long as you don't drain them flat and re-charge them a lot. They'll be ok for a while, but the capacity will slowly fall on each re-charge, reaching the stage where eventually the battery will be useless.
teejay Posted June 20, 2011 Author Posted June 20, 2011 How could I tell with a car battery how much charge is in it after it's been recharged? When going away with this, I need to be pretty certain that I will have sufficient life in the battery.
pcstru Posted June 20, 2011 Posted June 20, 2011 How could I tell with a car battery how much charge is in it after it's been recharged? When going away with this, I need to be pretty certain that I will have sufficient life in the battery. A normal car battery might be OK on a solar installation that is not doing much at night (i.e. it is rarely discharging below ~80%) but for your application you will be discharging the battery significantly and for long periods between recharges (5 days) and then (presumably) the battery will sit around for ages doing nothing before being put to use again. I wouldn't recommend a car battery for that. Worth mentioning 'Optimate' chargers will keep a battery in good condition, although they are not intended for fast charging (something anyway to avoid with Gel cells) but rather battery maintenance (ok, motorbikes sitting in garages over the winter). Uselessly (for a Gel battery), you can quite accurately test the charge in lead acid batteries by measuring the specific gravity of the electrolyte. Otherwise you can estimate it based on the open circuit voltage or the voltage into a load, but the results can vary quite widely depending on temperature and failing batteries can give misleading readings. 1
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now