Here's some notes I saved from the BB600 email list we used to have.I think most of the batteries were bought by Tim Humphrey? from a military auction back around 2003. I drove up to New York with a Uhaul trailer to pick up several hundred at Tim's house. "For the Good of the Order, I'll post this communique from Mike Phillips, who is no longer active on this list. His bb600 S10 pickup may have more nicad miles on it than any other vehicle in the group...He's posted some good nicad maintenance tips and photos on his blog at http://rotordesign.com/blog/category/truck1/ Bjorn and other newbies- the point that cell electrolyte levels can drop 1/2" in 30 minutes. That could certainly explain one of my previous over-watering incidents... Cheers,Jaywww.karmanneclectric.blogspot.com
-----Original Message-----From: Mike Phillips <[email protected]>To: Jay Donnaway <[email protected]>Sent: Mon, Jun 6, 2011 10:34 pmSubject: Re: bb600 Nicad update Guessing only causes problems. Torque wrenches are cheap. Ruin just one cell, and you could pay for a torque wrench. I have 2. One for the BB600's and one for the military 10mm. Cheap investment. The cells have to dead shorted for 24 hrs per the manual in the files section. They can put out 5 amps at 0.25 volts for hours on a dead short. So using bulbs won't get them there. Cleaning with vinegar is about a once a year process. Otherwise just use papertowels sprayed with vinegar to wipe the tops off. If the cells are not fully initialized and fully charged, the koh level won't rise fully, so you won't see it drop much. Per the manual they have to be over charged 10-20% for the cell to actually get to 100%. Both plates don't charge at the same efficiency. Go ahead and post it. I am sure I posted it before. Mike From: Jay Donnaway <[email protected]>To: [email protected]: Monday, June 6, 2011 8:30 PMSubject: Re: bb600 Nicad update Wow Mike, I've got the wrench, but will confess to using it to 'get the feel', and then proceeding by hand in cramped quarters....Yep, those slick stainless clamps have bit me- I may have also created a weak spot by designing the clamp shorter than the cells to avoid shorts, which leaves the sonic weld between the cell top and case exposed. All of the cells that have failed burned holes through the case at that point, even when it's apparently not the shortest path to ground. If you have more detailed photos of the insulative wrapping technique, that might be a good option to improve safety without scrapping my special clamps! I've zeroed out the pack twice, by driving it down, then running two 120V light bulbs in series, and then using old incandescent christmas tree lights to zero out any individual cells that still show voltage. (100 lamp strings= 1.2V/lamp). However, I thought that these big flooded cells were free of the 'memory effect'. It's been a year since I zeroed out the pack, and I've been only getting 22 amp-hrs out of it this winter. I recently got a 25 amp-hr run, and attributed that to warmer weather! By hottest in the very bottom corner, you do mean the Very Bottom, eh? I've never checked temp at the bottom of a cell, assumed that the hottest part would be up top or around the posts.I'll look for one of those pumps. My bulb syringe is fast, but still tends to drip, and then it's an exercise to wash the pack with a vinegar solution, rinse with water, and then vacuum it, blow compressed air, and finally air dry it with the covers off for a day or two... I think your biggest revelation tip must be watering with the charger on! I've done it with the safety disonnect out as an extra precaution, but hadn't noticed that the electrolyte level drops that fast. Must be why I've never had an eruption on the front pack of 70 cells, which is the first one I water, right off charge! With your permission, I'll post this to the bb600 discussion list. Thanks,Jay -----Original Message-----From: Mike Phillips <[email protected]>To: Jay Donnaway <[email protected]>Sent: Mon, Jun 6, 2011 7:54 pmSubject: Re: bb600 Nicad update Hi Jay, Do you have an inch-pound torque wrench for your cells? 99.9% of the EV community does not. This how cells get ruined and cars burned to the ground. I never wrap my cells in metal. They are always wrapped with mylar or something insulative then contained by metal. You may have had a hard ground fault and they got hot since the stainless was used as a shorting bar. Koh is extremely conductive. These cells usually get hottest at the very bottom in the corner of the 3" wide faces. Mostly from overcharging. My overcharging is from 100-300 amps of regen. You don't have that issue. So bring them up to 1.5-1.6v then shut them off. You will have to run them down to 0.0 volts to erase the memory. These cells get the memory effect badly. Watering is done with a MarkX electric hobby pump for model aircraft. Runs on 12v. The version I have has a fwd/rev switch on it. Makes filling 250 cells much faster. About 4 hrs. Don't spill any fluid between cells. It builds up to a ground fault. Reverse on the pump sucks the koh/water back up into the tube slightly so none drips out going from cell to cell. This is the best and fastest way of all the ways I have tried. The only time to water them is when they are 100% fully charged. No other time. That is when the koh level is highest. I fill mine to about 3/4" from the top at 100% charge. That is way higher than normal. They aren't going into aircraft. I also cut the tube off of the cap that extends down into the cell. In fact, I water my 250 cells with the charger running. I have to do this because the koh level will drop 1/2" in 1/2 hour. You have a qty of cells that you might be able to shut off the charger and do them all in 10 minutes or less. A123 modules are under test now. I didn't plan on selling them. But maybe if others own them we can get more data that way. Each module will require monitoring. Mike From: Jay Donnaway <[email protected]>To: [email protected]: Monday, June 6, 2011 3:51 PMSubject: bb600 Nicad update Hello Mike, I hadn't checked your blog in quite a while, and want to say thanks for the updates with good data on nicad maintenance. I'm hoping that you can help with a couple of questions. How did you lose a few cells to shorts? I've lost a dozen cells in incidents such as was described here...http://karmanneclectric.blogspot.com/2009/08/pop-go-nicads-not-quite-yet.html What tool do you use for watering the cells? I use a large bulb syringe with the tip cut so as to make the water level lower than the top of the 'venting slot' in the molded V under the fill cap. (Fill with water, then pull back until it sucks air.) Since those incidents with shorted cells, I've been probably under-watering to avoid spewage, but it's time to water again, and I want to get the optimal level this time. Also, any merit to adding mineral oil to the cells to cut down on foaming? It looks like you're charging to 1.6 vpc peak. Did I read right that you only maintain that voltage for a few minutes? Lastly, good luck on the A123 build. Do you plan on offering those 20-cell modules for sale once you've worked out the bugs? Thanks,Jay Donnnaway200-cell Karmann Ghia(with ten currently serving as the house battery)" On Sunday, May 4, 2025 at 10:33:15 AM EDT, John Lussmyer via EV <[email protected]> wrote: On 5/3/2025 11:08 PM, EV--- via EV wrote: > A friend here in Tucson bought a bunch of them he was going to use for > his conversion, then decided to use Lithium. He gave me one so I could > size it out for my conversion. After I thought about it, I realized > that they were just too high maintenance for me so I said no thanks. > > John - I still have that one and if it would be helpful you can have > it. Let me know. I don't think it's worth the shipping cost. (and probably hazmat issue) I should have plenty to do what I currently have plans for. Initial charging on the 32 cell pack found all were charging - except one that just sat at 0v. seems to be shorted. I'll swap that one out today. _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/ -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20250504/66bb620a/attachment.htm> _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
