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My husband has just bought a Jaguar i Pace battery pack, and hopes to use some of the modules in a motorcycle and trike project. Can a normal 72v or 96v lifepo4 charger, charge these cells, as available on ebay or similar, as the individual modules contain 12 cells per block, and most of these chargers state a 32s on 96v or 22s on the 92.4v charger the reason i ask this, is information seems a bit thin on the ground on the i Pace modules, and not sure if each module is 11v not 12v when fully charged, so 92.4 charger may be the best option for battery life, even if charging a little shallow. The chargers state for 20-120 ah battery pack? if as will be the case, he builds the larger pack for the trike, will it still be ok to use, just take an age to charge. Finally are their no variable voltage chargers on the market, to enable you to simply dial in your needs, till he has it all set in stone. He does have a Brusa charger, but does not understand can bus as yet, is there anyone in the north west UK who could guide, configure, and would this be the best option, other than it wont fit on the bike, and only suitable when back at base, but with a min of 6 modules hopefully 8 it will be over a 20kw pack so hope to get 200 miles as a min. Thanks in advance yours Dave
 

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The I-Pace modules are not LiFePO4. Even if they were, properly charging a high-voltage EV battery isn't just a matter of setting a target overall pack voltage and letting it go. To do this properly, you need a battery management system (BMS) which monitors the voltage of each group of parallel cells and the temperature of the pack, and controls the charger.

The I-Pace modules do have 12 cells, but in a 3S4P configuration. They appear to have roughly 56 Ah cells, for about 222 Ah module and pack capacity. The nominal module voltage is 10.8 V (3.6 V/cell and 3S). If you don't completely understand what this means, please learn a lot more about batteries before applying power to anything.

At 12.8 kg each, 6 to 8 modules seems like a lot of weight for a motorcycle.
 

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Probably best to break the modules down, capacity test each cell for go/no-go and re-assemble into the layout suitable for your use case.

Say the good ones average 50Ah remaining capacity, you could choose pack capacity of 50Ah, 100Ah at 2P, 150Ah at 3P etc.

The voltage you desire depending on the motor/controller you choose will determine your series count, so 20S gets to nominal 72V.

That charges at 82-84 similar to 24S LFP.

Best to get a good charger that automatically self-terminates, and allows for the CV voltage setpoint to be user adjusted. Satiator is a good example.

A BMS can handle the charge control, but usually just act as a safety failsafe for when the charger regulation fails.

Cell balancing can be done by a BMS to some extent, but make sure you can watch the per-cell/group voltages so you can observe the process.

If you do keep the 3S modules as built, and have a connection method that lets you dis/re-connect each cycle, charging and balancing can get done at the same time every cycle using relatively inexpensive PSUs + hobby chargers.

But then your pack-level voltage will need to be an increment of 10.8Vnom, e.g 75.6V or 97.2V
 

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Probably best to break the modules down, capacity test each cell for go/no-go and re-assemble into the layout suitable for your use case.
I can see testing at the cell-group level, but you could just test capacity at the module level and monitor cell-level voltages to check that the groups are reasonably balanced. These modules presumably have ultrasonically welded pouch cell tabs, like every other pouch cell module comprised of pouch cells; breaking all of the welded connections and having to rebuild them all is a lot of work, with risk of cell damage.
 

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Yes but as stated, at 13kg for just 3S, going to be to heavy
True, but I would say "13 kg for 2.5 kWh"; changing the configuration won't change the energy density or the resulting total mass for a target energy content. The desire appears to be for more than 20 kWh:
... with a min of 6 modules hopefully 8 it will be over a 20kw pack so hope to get 200 miles as a min.
At 2.5 kWh per module 6 to 8 modules will be 15 to 20 kWh (and roughly 77 to 102 kg); that will be true regardless of series and parallel configuration. The series versus parallel configuration is relevant to pack voltage, not energy and mass... and whether or not 6 to 8 times 3S is suitable depends on the motor choice.

Is 100 watt-hours per mile reasonable for a motorcycle?
 

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The voltage will need to be configured to suit the motor+controller, and to allow the top speed desired.

If that is the top possible speed, might even be over 96V (27S, 9 modules in series)

so then you're over 200 kWh already with 4P

but that's a damn big pack at 115kg.

If that high a voltage is not needed, will be proportionally lighter.
 

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Hi Brian John
Thanks for your input, I would be very reluctant to break down the modules to harvest the pouch cells, and as the pack is a late 2020, they should be more than just ok, and all the modules are currently sat at the same voltage. I agree they are heavy, so much so, i have decided 6 cells only at the moment, yet still a lot better than leaf cells weight wise, and i would struggle to use Tesla modules as is, in the bike, and but they would probably be fine in the trike. Regards the bike, yes 90 watt-hours is average, but i am constructing an FF or feet forward type vehicle, ie a very low seat height, like a chopper, but with OUT the extended forks, and by using a full fairing, the smaller lower footprint results in much reduced drag, to lower the power requirement even further. I am aware the actual cells are not Lipo but i assumed the charging rescheme was the same, and hoped a basic charger would suffice for now, i just want to make a start. The individual modules are of a very high quality, and well built, as should be expected from a vehicle manufacturer, and i thought it a more practical alternative, than to placing an order online for an unknown 12v lifepo4 std battery. Eventually when everything is sorted, i will then probably go over to a custom pack, and i can then finally fit the pack under my Peugeot Boxer van conversion, which currently has a 50 kw? calb cell battery at approx 1.5 ton including the box, so its nearly double the output, for half the weight, so a big improvement. Either way, what little i do know, i will feed back in via posts as to my progress and outcome, to help steer others in the right direction. Thanks again yours Dave
 

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OK so ~65V midpoint,

may not be as fast as you'd like

74V cutoff charging, could get a basic PSU or DC converter and add an HVC circuit

LVC at between 55 and 60V depending on your C-rate and how important lifespan is to you vs maximum range
 

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I agree they are heavy, so much so, i have decided 6 cells only at the moment...
Of course you mean 6 modules, of 12 cells each.

I understand wanting to use salvaged production EV modules rather than buying new modules (especially from a questionable source), but a vehicle such as the I-Pace with such a large battery (90 kWh) is not a great choice because you end up with such a low voltage for a given energy capacity. For instance, a BMW i3 uses a somewhat lower overall battery voltage but with much less capacity, so its 8 modules run about 45 volts each are are similar in size to the I-Pace modules. The Renault Zoe also uses smaller modules with more cells in series.
 

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OTOH paralleling high-voltage packs is going to result in imbalanced flow rates.

To me, starting with separated cells is usually best, if not actually required well worth the trouble
 

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OTOH paralleling high-voltage packs is going to result in imbalanced flow rates.
Right - I'm certainly not suggesting paralleling modules (although it works well in the special case of the original design of Nissan Leaf modules, because they provide access to every cell level with high current capacity). If you can find the right capacity of module, you don't need to either parallel them or reconfigure them.
 

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David, do you have any plans for the remaining modules from the Jaguar pack? I'm looking at options for my Hillman Minx conversion and the Jaguar modules look like a good bet.
 

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I'd like to see the Hillman conversion. A long time ago I had a Commer Cob (imported into Canada by Chrysler IIRC).

Sent from my SM-T380 using Tapatalk
 

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David, do you have any plans for the remaining modules from the Jaguar pack? I'm looking at options for my Hillman Minx conversion and the Jaguar modules look like a good bet.
Hi Frank
I bought the i Pace pack primarily for another project, to fit into a van, and need all the modules, and possibly even more off. I am only using a few now carefully, to trial in my electric motorcycle, and also my electric reverse trike, before refitting back into the original battery casing. I do have a large qty of Calb 220 ah cells available if interested, and also over 50kw of new laptop battery's still in original wrapping, which i would prefer to sell preferably as a whole if possible. Subject to how the trials go, i may invest in a second i Pace pack, and would then require approx half the pack. If this or the other cells, is something you may be interested in please email me on [email protected]. Dave
 

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Thanks for letting me know. I'll be wanting a majority of the modules in a pack to make up the voltage I need to drive a Leaf motor. I'll probably have to follow your lead and buy a complete pack.

The Minx conversion is in it's early days and I'm still pulling things apart to allow upgrades to the suspension, running gear and brakes. Despite being a classic, the aim is to use the Minx as a daily driver so it'll need the upgrades to fill that role. Once I've made some headway I'll post some photos for those who are interested.

Have you decided on a BMS to go with the Jaguar modules in the van?
 

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I'm looking at options for my Hillman Minx conversion and the Jaguar modules look like a good bet.
I'll be wanting a majority of the modules in a pack to make up the voltage I need to drive a Leaf motor.
These modules seem like a strange choice in this case. They're only 3S and 12.8 kg, so you would need 32 to reach the 96S and 360 Vnom of the Leaf configuration; that's 89% of the full I-Pace pack, which is 80 kWh and 410 kg, and seems like a huge battery for a Hillman. Is the plan to run only the minimum voltage needed to drive a Leaf motor?
 
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