Basics on getting the Li battery out of a VX-1

Too stupid to answer--I get it. Well, I "screwed my courage to the sticking place" and took the covers off. Who knew there were just four little white plastic plugs, easily removable, holding it on. And I didn't die yet, which is good. I'm very excited to finally get into the innards, after reading on and off here for years but feeling this stuff was over my head.

So, now I'm looking to find how to determine which cells to replace and how to deal with getting them into the proper state before hooking everything back up. A random check finds cells in the bike reading between 1.97 and 2.70, with one cell so far obviously very low. There is little uniformity among the cells, so much so that I couldn't say what the most common reading is. The ten cells in the replacement pack I bought are all near 3.23.

Initial investigation makes me think I need to get a DC charger that gives me close control over amperage and voltage, perhaps even charging each cell individually. Is this a half-ass way to begin with a balanced battery? I found a reference to Mik explaining in detail a lengthy process for charging, testing, discharging, etc., but I haven't found it yet, and anyway, I'm assuming the method will be for NiMH instead of Lithium.

I haven't removed the batteries, and I haven't tried the procedure for removing individual cells, but it looks straightforward enough. I intend to try to do it without taking off the metal bands unless someone advises me to use Mik's method.

If anyone wants to help, I could use advice on:

1) How to determine which cells to replace. I will likely use all ten of my replacement cells, assuming they are all in better shape than any in the bike.
2) What to do about getting the cells close to the same charge. Do I need to do this before hooking it all back up? Would it be better to discharge the new cells or charge the ones in the motorcycle? How do I do either, including . . .
3) Do I need a charger and what is an affordable one that will be adequate?

I'm still wondering whether the BMS on this motorcycle actually monitors each cell individually. It seems to be connected to one terminal of almost every cell, but not every one.

I see my photo shows a sloppy use of my screwdriver as a prop. Oops. I quickly retired that method before any accidents.

I am taking tons of photos to help with getting it back together. I would be glad to document this process for the 2009 Li VX-1 but assume it has been covered and I just haven't found it yet.

Thanks for that feedback, MEroller. I'm sorry to hear that I won't find much here about Li Vectrix. In that case, I'll write this up when I'm done.

I had decided this morning to do just that--put it all back together and charge it. I have no idea when it was last charged. Then I figured I should make a record of the voltage of each cell first, thinking that would give me some information when I measure them all again after a charge. In doing so, I found one cell at 0.17 with all the rest between 1.51 and 3.04. Now I am wondering whether I should change the obviously bad cell out before running a full charge. My idea is to drain one of the new(er) cells down to about 2.8, which is at the high end of the range I found with the other cells, before replacing the bad cell with it, then run a full charge using the Vectrix charger, then read all the individual values again. That will tell me something, I think, about each cell's health (unless the BMS somehow is creating variable charge). I'm not sure if it is necessary to replace the bad cell first, but my fear is that it will cause some kind of harm and I figure that one will definitely need to be replaced anyway. I have no idea whether it is necessary to match the new cell more or less to the other cells before charging.

It looks like I need to get an iCharger. Thanks for that. And it looks as though the iCharger offers a way to discharge, so I'm thinking I'll wait for one to arrive, drain the cell I'm going to install down to the range of the other cells, then do a full charge using the Vectrix charger.

Piotr said he would send me the updated firmware, but I seem to have lost his email address. If anyone has that, I would appreciate that as well. It looks as though I need to send Sandy an email to find out if he has written anything for this version of the Vectrix Li.

I really appreciate the help, especially the lead on iChargers. I have a learning curve ahead, and one reviewer complained that the manual is not that helpful for the beginner. For starters, I don't understand how the different models are rated for different numbers of cells. Wouldn't the number of cells the charger can handle depend on the voltage and wattage of each cell? I also don't understand how it can balance cells and measure internal resistances of each individual cell unless it connects to the terminals of each cell rather than the pack as a whole. Perhaps the answer is that it does in fact connect to each cell, which explains why the spec is number of cells rather than total voltage and wattage. Anyway, I'm not looking for a tutorial--I need to do some research. But I did need a lead on the iCharger, and any further clues will be appreciated.

I'm having trouble even being certain of the battery chemistry of these batteries. I think it is LiFePo4. Going on that assumption, I just read that the absolute minimum discharge voltage for a LiFe is 2.0 volts. If true, this means that I have 5 cells that definitely need swapping out.

So, the question is whether MeRoller is accurate in his assertion--any BMS attempting to balance this pack should be in the loony bin. I am wondering two things:

1) Would attempting to charge the pack as is, with 1 practically dead cell and 4 others lower than 2.0v, cause damage to other cells, the charger, or the cosmic vortex? Charging first would have the advantage of bringing the healthy cells back up close to the new cells before installation.

2) If I change out the 5 low cells before charging with the Vectrix charger, do I need to discharge the new cells down to the range of the other cells before installing them?

Either way, I'm thinking I need to run a couple of charge/discharge cycles with the Vectrix charger before starting the tedious manual balancing, hoping that it will be closer to balance when I begin.

Does this gross imbalance mean that the BMS was not doing is job, or is it possible that this is simply the result of variable discharge rate during a long time without being charged. (I have no idea how long this bike sat around unplugged.)

It would be good to fix up a balancing situation like you have, MeRoller. I'm looking at the iCharger 1010b, which seems can balance 10 cells at once, but first I'll see if I can find an explanation of the kind of rig you mention simple enough for me to understand. If I can get the idea of it, I'm sure I can execute the process carefully enough.

Now that I'm finally getting started, I have hopes of gaining some proficiency here. The learning curve is tough at the start, so that even a little help goes a long way. Thanks very much.

Kocho, I'm following your conversion process. If I can get this lithium on the road, my next project will be to do a similar conversion on my 2009 NiMH.

One final thing people may find interesting. Jim, that solar guy who bought a bunch of batteries at the auction, had batteries which have been used in Vectrix in a combination of 6- and 7-cell packs. I don't know any other way to identify these batteries, don't know their chemistry even, but I will tell you that Piotr has agreed to write software for a BMS for them, which he said would take him 6 weeks, and that Piotr said they would yield a range of around 90 miles. I'm wondering how this looks in comparison with the Leaf batteries, or whether perhaps they ARE Leaf batteries. Anyway, this route could be an alternative to the Leaf route. I appreciate that I'll be able to learn from the efforts of others before turning to that job.

For the record, I've been doing some reading and it seems I should change out the cells below 2.0v before charging.

From Battery University:

Do not recharge lithium-ion if a cell has stayed at or below 1.5V for more than a week. Copper shunts may have formed inside the cells that can lead to a partial or total electrical short. If recharged, the cells might become unstable, causing excessive heat or showing other anomalies.

But this straightforward statement is confused by the fact that most discussion of "lithium ion batteries" refers to a battery type with nominal operational voltage of 4.2v as opposed to the nominal operating voltage for the LiFe ion battery of 3.5v. Therefore, I'm not certain what low voltage is dangerous for these cells. Furthermore, I read elsewhere that "lithium ion batteries" should never drop below 2.0v, again with the confusion of not knowing which kind of lithium ion battery they were discussing.

As of now, I intend to swap out all cells reading below 2.0v before charging with the Vectrix charger. The question remains whether I need to discharge the cells I am putting in to be in the range of the other cells before charging the entire pack with the Vectrix charger.

I just received the following advice, which I will follow.

Replace every cell reading below 1.0v (just one cell). Then charge using the Vectrix charger until the new cell reaches 3.7v. Then measure all the other cells again. Makes good sense to me, because it guards against overcharging the new cell, which is starting at a higher voltage, and it also gives the BMS a chance to do some balancing. Depending on how things look at that point, I can try doing another discharge/charge cycle to see if things come into closer balance. In the end I expect to be charging individual cells.

Does anyone know whether the 2009 VX-1 li has a shunt resistor built in or still needs an ICL? The engineer who bought batteries and several motorcycles without batteries at the auction flat-out didn't believe me when I warned him that he would need to rig something up. This made me wonder whether Vectrix eventually made it easier on themselves and us by including one on later models.

Over several hours I managed to get a battery apart, swap out the bad cell, and get it back together. Every single cell in the pack was swollen on the wide side, so much so that it was quite difficult just to get the packs in without the spacers. Still, they all register above 2, with most reading closer to 3, so there is life left in them.

Double post. What's with all the double posts? After I post, I always receive "Page Failed to Load", but I've learned to wait and the post will appear eventually. This time it double posted anyway.

Sad, sad news. I suspected as much and almost didn't put them back together. Now I wish I had just bought four batteries. I think I'll charge it up and see what happens, but I've heard this said before. There are also color streaks on the casings that could be interpreted as over-heating.