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I'm sorry, but this is NOT a good idea. Just to be clear, a 2P16S battery is 16 pairs of cells in series. Each cell in a pair is connected to the other cell, both positive and negative. The BMS in this case can only read the voltage of each pair. Because they are in parallel, it is reading...

Oh, and in case you want to know how this happened, back in the day Honda (and early Toyota) hybrids had packs made from 120-240 cells in series, but the BMS only monitored them in strings of six cells. As the cells aged, the internal resistance of individual cells would vary, and the vehicles...

I'm specifically taking issue with the stated goal of matching the highest capacity with the lowest and then the 2nd highest with the 2nd lowest. Here is a research paper that tests this fairly thoroughly with LFP cells. One of the unexpected issues they found that the current between the...

@TorC my experience is primarily with NiMh cells. NiMh cells have the ability to be driven negative (into cell reversal), which destroys them, without risk of thermal excursion (because they radiate the heat out nicely). While I see your and @Ampster points about the voltage of the smaller...

I'm talking about when the smaller cell has reached terminus (below the knee) and the other has not. Obviously if you are not going below 20%, you are not going to stress it as much, BUT you will still throw the cells out of balance very quickly. For example, let's try an extreme: 100Ah and...

Up until 2012 at least they both still used 7.2V NiMH although Toyota used a six-cell prismatic design instead of cylindrical. Ford Escape Hybrids used the same cylindrical sticks just packaged slightly differently. Mind you this is pretty much every hybrid vehicle made worldwide from 1997 -...

I have two prototype LFP batteries each made up of 16 new REPT 100Ah cells. The company that made them did a poor job at laser welding the busbars on top and they’ve come off many of the cells. I’d like to save these 10Kwh of cells, but to do so I’ll have to somehow attach studs or busbars to...

So I received a 400AH 12V LifePo4 battery from a manufacturer in China. Fedex managed to drop it upside-down and the tape holding the cells together shifted. The battery is set up as 4P4S 100Ah cells. That's four sets of four 100Ah cells welded in parallel. There are no studs on the cells...

If tapping is in the cards, can anyone tell me how deep to go? These cells look like they have a raised terminal pad so more than 6mm might be reasonable.

I specifically chose a Rec BMS (Rec Q specifically) because it is compatible with a Wakespeed WS500 alternator controller via canbus and also Victron compatible. This way the 48V 100A alternator will not load dump if the BMS disconnects because the BMS will tell the Wakespeed to power down the...

That's why I'm going with a CANBus enabled BMS (Rec Q BMS). It can tell the auxiliary alternator how much power it wants, can tell the Victron Multiplus to stop charging, etc. It can control the big items to keep from tripping the contactor in most cases. I am twinning the (brand new) cells...

Auto manufacturers hadn't really figured out how to use lithium technology economically. Tesla Roadsters were one of the first (if not the first) automotive applications of lithium batteries and that was 2008. The Prius plug-in came out in 2012-2013 but that was a 4.4Kwh pack that weighed...