Opening the sealed maintenance free battery adding epsom salts, charging and resealing.
To remove the acid I used the hydrometer and dumped it into a plastic icecream container, took about six pumps from each cell to get out a decent amount which was about a litre, then took the acid and microwaved it for three minutes. (WARNING this is what I did, not what anybody else should do. please observe all safety warnings regarding ACID, GLOVES, MICROWAVE OVENS, and hostile partners or houseguests I in no way accept responsibility for any Darwinian behavior after watching this video.) then added 2 cups or 400 Grams of epsom salts to the acid solution and stirred till it all dissolved. Then using the hydrometer replaced the solution in the battery, caution should be used here as if the battery electrolyte level was correct before adding the epsom salts it may be too high once you start to recharge it, but in most cases the level should be alright, keep an eye on the level as charging and if necessary just suck some back out as the level rises. Excess solution can be disposed of by adding a bit of sodium bicarbonate and diluting with plenty of tap water or just lots of tap water letting the container fill and overflow for a few minutes and it will be so dilute it will be harmless. The acid solution is only 35% to start with so by the time you fill a 2 litre container with the excess in it will only be 2%, continued flushing will dilute this to nothing. Updated video here https://www.youtube.com/watch?v=65yz6qwK_x8
Post time: Dec-03-2016