| Gallery, Projects and General > Project Logs |
| Alum battery conversion. |
| (1/8) > >> |
| DavidA:
HI, I don't know if this has been done here before. But here is what I intend to do. I was watching a series if videos on the recovery of lead acid car batteries. Here is the link.. definitely interesting. So, I have a number of old batteries and decided to give it a go. Today I dug out a battery that has 9.9 volt across the terminals. It was first charged in 2000. So it is 14 year old. I picked this one as even a flat battery should have 9 volt if it isn't damaged. It is a MotorCraft Superstart EMF 560 030 060 W. 12 Volt 590 Amp 60 Ah. The start conditions of this experiment are. Cells checked for electrolyte. Found to be all at top of plates. Added a bit of distilled water to each to ensure plates covered. Terminals in reasonable condition, non of the hard crusty layer often found on the + terminal. Cleaned them up. Connected a small charger (max 6 Amp) with a 5 Amp moving coil meter in circuit. Switched on. Initial charge rate 0.1 Amp. 11.7 Volt across the terminals. Now , this voltage is too low. Should be around 14 Volt at first. So the charger is suspect. Tomorrow I will buy another small charger. I have a big charger, but don't want to use it for this test. I'll keep going out to check on progress this evening. When the battery has been charging for 24 hours (4 PM tomorrow) I'll record the numbers then it is a matter of awaiting the Alum before proceeding. Dave. |
| awemawson:
I can see that draining the old acid, and flushing with baking soda may well knock the hard suphates off the active lead plates - it's those hard suphates that give the battery a high internal resistance. Also debris falling off the plates accumulates in the bottom of the battery, shorting out the positive and negative plates and self discharging the battery. Again flushing out will get rid of the debris. But what the chemistry of filling it with alum solution is I have no clue. As I understand alum is hydrated potassium aluminium sulphate. I'd be interested to see what charging and discharging characteristics have been created. I have a feeling that flushing with bi-carb followed by water, and then refilling with the correct strength of sulphuric acid would be more effective. Note that that was a deep discharge 'leisure battery' he was using, that would have extra space below the plates. |
| DavidA:
Yeah, The usual procedure is to drain out all the acid then refill with 1.250 SG acid. Recharge, check SG and repeat until it holds 1.250 SG I agree that there will be room beneath the plates for dislodged sulphate. But it is just a bit of fun, so it doesn't really matter if it fails. Mind, I will be chuffed if it does work. How come the Americans are so much more into this stuff than we are ? Dave. |
| awemawson:
You used to be able to buy 'battery reviver' tablets in the UK - the pages of Exchange & Mart were full of them back in the 1980's . I suspect whatever improvement they made if any was by physical desulphation. Now in my youth (an awful long time ago :bugeye:) I used to revive ex WW2 NiFe cells quite successfully by flushing and re-filling with potassium hydroxide solution. |
| DavidA:
I also have used those tablets. Can't remember if they worked or not. The web is replete with a variety of de suphating methods. Pulsating high voltage DC seems to be a favorite. Just been out to check my battery. Same Volts and Amps as before. The worst thing you can do to any rechargeable battery is to allow it to it unused and not charged. Dave. |
| Navigation |
| Message Index |
| Next page |