| Author | Message | ||
     Bob UK Unregistered guest Posted From: 94.197.122.73 |
My bro in law has given me a large 200 amp hour leisure battery from his caravan. He has brought a new one. The battery he gave me is sulphated up and has only 0.3v. I have read a few sites on the web describing recovery techniques. These in the main involve upping the charge voltage from 14.4v to say 18v. Which requires a big charger which I have. I have so far in 6 hours got the open voltage from 0.3v to 4.5v. I suspect that it's going to take a 100 hours to fully charge it, that's if it actually will charge. The date code is March 1995. I shall let you know what happens. (Message approved by david_gore) | ||
| Bob UK Unregistered guest Posted From: 94.197.122.80 |
Up date on battery. The amp hour rating is 110 not 200, the 200 is a part number. I stopped charging at midnight because leaving a battery charging with 18 volts being stuffed in it unattended is dangerous and a fire could result. At 9 am the voltage had drop back to 0.6 volts. The charge has melted away deeper into the battery. So back on 18v for 8 hours and the battery lights a headlamp bulb 55watts dimly for 15 seconds. The battery has got less than 1% of its capacity. I think we as buyers of car batteries are being ripped off. This battery is not well made, for a deep cycle battery it has thin plates. Also it appears that the plates go to the bottom of the case leaving no room for sludge. I suspect that it's a starter battery with leisure labels. It's twice the size of a shadow battery and twice the amp hour. A deep cycle battery of 110 amp hour should be much bigger. If you require a deep cycle for leisure use then buy 2 six volt golf cart batteries and look after them according to instructions and they will last 10 years plus. My next recovery technique is to lay a thick piece of wood against the case end and twat with club hammer to knock off the sulphate. If that doesn't work then I will take it to bits and manually clean the grids and remove nasty sludge. Would lemon juice do for electrolyte. Incidently the lead acid battery was invented by Dr Plante of France in 1856. The battery was spiral wound like optima batteries. Within a short time others developed it and by the first world war the battery was about fully developed and since then they have been pretty much the same, New developments usually turn out to be something tried before but not taken up. (Message approved by david_gore) | ||
| Jan Forrest Grand Master Username: got_one Post Number: 717 Registered: 1-2008 |
I have a pair of traction batteries of that capacity on my mobility scooter. Obviously I had to modify the battery tray and bodywork to fit them, plus they take up half the footplate. I've not tested them for ultimate range, but I can ride into town (2.5 miles), around town to check availability and prices (ditto), around town again to purchase what I want and finally back home. Total distance traveled = approx 10 miles and the battery meter will have only dropped by one bar out of 8! I've had them for 2 years and they still take a full charge. All my old batteries are used in various locations - garage, workshop, etc - with either a permanent trickle charger of a few milliamps or 12 volt solar panel to maintain a charge to power a small alarm and/or battery flourescent lighting where mains power is impractical. As for who invented the lead/acid battery: Sealed jars similar to Canopic Jars have been found in Ancient Egyptian tombs containing lead sheets and dessicated organic residue which may or may not have originally been wine or wine cider. Modern copies have been made that actually generate a tiny current/voltage which is enough to use for electroplating small items. The jury is still out as to what use might have made of them. | ||
| Randy Roberson Grand Master Username: wascator Post Number: 338 Registered: 5-2009 |
at work we use large batteries for uninterrupted (i.e. emergency) power supply for control systems. They are called submarine batteries but if that is indeed what they are, I don't know. They are in large rectangular glass jars, and can I suppose be dismantled for repair and maintenance. They seem to last a long time. We also use some modern, gel-cell batteries which look like sealed auto batteries, for this same purpose. Maybe the old style batteries in the glass jars are no longer being used, I don't know. The gel-cell batteries have to be replaced about every 5 years, or they seem to fail and sometimes cause a small fire if kept in service too long. If your Dad is replacing the batteries in the motorhome (caravan to you), try to get there to help before he dismantles all the cables without sketching the layout of the connections. These things do not react well when improperly connected. Yes, I had this experience. | ||
| Bob UK Unregistered guest Posted From: 94.197.122.93 |
My disability scooter has a lithium battery. Which has a plug socket for charging and a circuit breaker. Underneath it has contact pads which rest on spring loaded brass contacts. The battery connects itself, when dropped in the cradle. 24v. It has a dedicated charger, specially designed for the battery. When the green light stops flashing its ready. At the moment the scooter is not being used, so I leave the charger connected to a timer which turns on for 2 hours a day. It is not possible to damage the battery like this. The battery costs £110 and lasts 21km/6kmph or 3.9 mph to the start of the dreaded red zone. I only allow half way into the Orange zone. If charged and just left the battery even after a month is still good to go. With cars I think due to the amount of amps required, that cars should have gone to 24v systems years ago. Modern luxury cars have 130 amp alternators which is huge. A 12 volt starter needs 200 amps which means either a big deep cycle battery or a thinner plate starter battery. 24v starters only need a 100 amps which a smaller deep cycle battery would easily cope with. The only extra cost is double the amount of battery cells. Not necessarily two batteries. Some high output alternators have water cooling. Which costs more. I had a black cab that had two large 6v batteries in series which were deep cycle ( standard fitment) They cost £45 each ( 1982). The lights can be left on for hours and it still started. (A legal requirement of a black cab). Most light aeroplanes are 24v (28v they call it). Some luxury cars now have two batteries and split charging. Which has got to be more expensive than just going 24v. Most car alternators with a change of the regulator will work at 24v because only half the amps is required the alternator has an easier time. I think 12v has become traditional. 9 cells and 18v could be used. 12 was ok when it was just ignition and lights. Today I was talking to a guy who's into old brit bikes. The 6 volt motor bike batteries are miniature deep cycle batteries. But the 12v ones are starter batteries which don't last. So if the bike has no starter motor he fits 2 6v batteries. All this battery stuff makes one paranoid about car batteries, fortunately, they are cheap. So panic over. (Message approved by david_gore) | ||
| Bob UK Unregistered guest Posted From: 94.197.122.88 |
Posts getting lost in the ether. Telephone exchanges use these, they call them jars, a bit like those Egyptian batteries. They are square heavy glass jars with glass lids which are not sealed. They are 12x24x24 single cell 2.1v. They are in banks of 24 for 50v. The phones run on these batteries and a mains charger continually tops them up. Should the mains fail then the chargers stop and it makes no difference to the phones. If the power is off too long they start diesel generators. We used to have a battery shop when I was an apprentice and they used to melt old plates and pour out new ones in a simple open mold. Then fit the whole lot back in the case and seal it with pitch. Then charge and discharge for a few times to pock mark the plates for more surface area. These batteries were twice the size of a modern battery for the same capacity modern one. I believe submarine is used like Hoover as a term for any large lead battery. Forklift is also used. I have seen submarine batteries and these were 4 cell each and need a forklift to move them. Two of these at home would be usefull. Some say that lead acid is out of date but in a static situation size and weight is not an issue and amp for amp they are the cheapest by far. Also 95% of lead battery is recovered and turned into new batteries. The greens have been promoting batteries for off grid living but what is not understood is that lead acid batteries require maintenance charging procedures which consume energy that is lost though heat etc. The efficiency is about 60%. Most off griders have continual battery problems. A set of glass jars from an exchange would be good. Another option is super capacitors. These when charged stay nearer to charging voltage. Whereas lead batteries are about 2v behind for 6 cells. Which with cunning could paralleled to a lead acid thus boosting voltage. Mercedes Use a motor cycle battery under the pollen filter as a booster for low battery situations. If the system goes completely flat both batteries then most of the accessorys will have to be rebooted by Mercedes. Scary open wallet stuff. (Message approved by david_gore) | ||
| Bob UK Unregistered guest Posted From: 94.197.122.74 |
Update on battery recovery. I left the battery on charge for 40 hours total in 10 hour chunks connected pos to neg. This put about 2 % charge. Then I connected the battery up the correct way. This caused the battery to discharge fast in 2 mins. The amps started at 15 and dropped to zero ( dead battery) then the amps started to climb slowly to 5 amps and stayed there for 20 hours. A voltage test showed 12.1 volts. it's difficult to say in % terms but at a guess 25 % capacity. The next thing is to try to over charge it and get some heat in ( 35c is max according to the off grid guys) The idea is that the overcharge forces electrons into the sulphated areas which causes heat due to electrical resistance of sulphate. The heat causes the plate to expand which cracks the chyrislised sulphate. Then as the battery cools down the plate shrink. Also because bits of sulphate fall off the lead paste shrinks. Then put the caps back on seal the vent pipes and invert the battery upside down for a day. Little batteries are light enough to shake by hand. Batteries that are not moved or charged, will cause the acid to sink to the bottom. Static installations pump air into the battery like a fish tank. Charging mixes the acid. So when driving down the road the GENTLE movement of the vehicle helps. Viberation shakes the paste from the plates. So unsecured batteries damage them selves. Mot failure any way. By inverting the lumps of sulphate will be at the top where I can stab them or crush them with pliers. So far the off grid guys are right about battery recovery. one guy in Arizona has fish tanks with lead plates, he has 24 tanks for 50v. Fortunately he has a lot of wind and Sun and using inverters he runs normal house hold stuff like a washing machine and even aircon. He said that to live in the desert where there is no grid is not possible. I am jealous because his back yard is a 100 miles long. I bet Tescos don't deliver though. (Message approved by david_gore) |
