Hi David, Golfcart batteries have about 1/8" ridge around the battery fill holes, so it is very unlikely that once the small amount of acid flowed over that ridge that it made its way back, it was not a large wave of acid, since it could not flow faster than that the auto-shutoff jug was filling, which is a trickle. So, I am quite sure that no baking soda made its way into the cell. My concern is, now that I removed some acid from the cell to bring the level back down and avoid overflowing while charging, that the total amount of acid is lower than in other cells, so this cell will have a tendency to go flat before the others - not by a large margin, but a few percent. I tend to avoid the bottom 20% of charge anyway and floodeds are quite forgiving in general, also my pack seem to have been relatively well balanced while I charge it sparingly, so I will just need to be extra careful in the next weeks until I dare to put the acid back in (after fully charging, of course - no need to create an even bigger mess) No other cells were overfilled, as far as I could determine the auto-shutoff operated correctly all other times (and that is also why I was not on top of it until it failed to shut off).
I presume that you meant to say "unless it's very high in minerals" and luckily our water is the "softest" in the area. I grabbed the water report from the city and saw that our tap water has on average only 71 PPM (Parts per Million) total dissolved solids, of which 53 PPM calcium carbonate 12 PPM sodium The average Ph is 8.4 but varies between 6.5 and 9.4 since the total dissolved solids can vary between almost 0 and 109 PPM. That does mean that there are some impurities added to the cells, but not a large amount and since the amount of tapwater was approx 5% of the total fluid contents of the cell (my estimate) the total impurity level is about 3-4 PPM added total dissolved solids. I am no battery engineer though, so I do not know how bad that is, please enlighten me. Or time will tell... Regards, Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.info Skype: cor_van_de_water Tel: +1 408 383 7626 -----Original Message----- From: EV [mailto:[email protected]] On Behalf Of EVDL Administrator via EV Sent: Sunday, August 10, 2014 9:18 PM To: Electric Vehicle Discussion List Subject: Re: [EVDL] Flooded lead-acid ooopsie and how to correct best? On 10 Aug 2014 at 19:43, Cor van de Water via EV wrote: > I suddenly heard an agitated hissing from the baking soda on the top > of the battery, being eaten by the overflowing acid from that cell ... > I have put extra baking sode around that fill hole after closing it > carefully and I have since bought a plastic syringe with which I will > remove some fluid from that cell and store it in a plastic bottle > until enough water has evaporated from that cell to put the acid back > in without overflowing. > > The second issue is more disastrous ... I had used *plain tap water* > to fill my batteries ... I'm not a battery expert, but this is my take on the situation. I'm more concerned about the first accident, and the possibility that some of the baking soda dissolved in dilute electrolyte may have flowed back into the cell. This might partly neutralize the remaining electrolyte, in addition to it already being more dilute. I think I would be inclined to completely drain the electrolyte from that battery, or at least that cell, and replace it immediately with fresh 1280 SG electrolyte from a good battery shop. As for other overfilled cells, depending on how dilute the electrolyte is, they may have become somewhat acid starved. Thus the electrolyte will go flat before the grids do. This will set your (now possibly lower) maximum amp hour capacity. A hydrometer will tell you how much they differ from the rest of the pack. Assuming you see a significant SG disparity, I'd suggest monitoring those batteries as you drive. That way, you can stop when they reach 80%DOD, no matter what the other batteries are doing. That will reduce the risk of reversing them. Or, you could drain the electrolyte from them too, and replace it with fresh 1280 SG electrolyte. As for your accidental use of tap water, it's very high in minerals, I personally don't think that one watering with it is going to be all that harmful to the battery. I don't recommend it as a practice, however. Especially since I'm not a chemist or engineer, other views are most welcome. David Roden - Akron, Ohio, USA EVDL Administrator = = = = = = = = = = = = = = = = = = = = = = = = = = = = = EVDL Information: http://www.evdl.org/help/ = = = = = = = = = = = = = = = = = = = = = = = = = = = = = Note: mail sent to "evpost" and "etpost" addresses will not reach me. To send a private message, please obtain my email address from the webpage http://www.evdl.org/help/ . = = = = = = = = = = = = = = = = = = = = = = = = = = = = = _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
