Mach-E Battery Reverse Engineered

GoGoGadgetMachE

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My concern with Tesla's 5000 cylinder battery approach is recycling. It seems a whole lot easier to disassemble a pouch cell and extract the rare earths vs having to break thousands of batteries out of a plastic resin to get to them.
completely serious question - could they do the Leaf thing and just make them into, like, house solar batteries? I know that's not the same as recycling of course, but it at least means a life past the car.
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completely serious question - could they do the Leaf thing and just make them into, like, house solar batteries? I know that's not the same as recycling of course, but it at least means a life past the car.
Tesla already does this to some extent. Power packs that don't meet QC for auto use but do for PowerWalls are put into PowerWalls. Tesla has talked about this use for the power packs removed from Teslas as well. There's a video from a KY Congressman who nabbed a totaled Tesla and converted it's battery into use in his home solar installation.
 

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Nice reverse engineering! By my calculations, the cells are likely ~72Ah each.
 

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Nice reverse engineering! By my calculations, the cells are likely ~72Ah each.
Hey EV Lab, what does 72 Ah mean in this context? I need to know the voltage in order to calculate energy capacity. But voltage on Li-Ion changes with state of charge, so that Ah rating gets ambiguous/slippery. Can you just give a wH number instead? Back when all lead-acid batteries were always 12V, Ah was a way of stating energy content because everyone knew 12V.
 

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Hey EV Lab, what does 72 Ah mean in this context? I need to know the voltage in order to calculate energy capacity. But voltage on Li-Ion changes with state of charge, so that Ah rating gets ambiguous/slippery. Can you just give a wH number instead? Back when all lead-acid batteries were always 12V, Ah was a way of stating energy content because everyone knew 12V.
From the web:

"An ampere hour is the amount of energy charge in a battery that will allow one ampere of current to flow for one hour.​
An ampere is a unit of measure of the rate of electron flow or current in an electrical conductor. One ampere of current represents one coulomb of electrical charge moving past a specific point in one second."​

72Ah denotes the capacity of each cell. Wh is simple and easy to calculate. The LG Lithium Ion cell chemistry for any of the latest EVs are all very similar in voltage, which is a nominal voltage of 3.65V.

72Ah x 3.65V = 262.8Wh.

262.8Wh x 4 x 94 = 98.81kWh (where 4 = the number of parallel cells, and 94 = the number of series cells, for the extended range pack).

262.8Wh x 3 x 96 = 75.69kWh (where 3 = the number of parallel cells, and 96 = the number of series cells, for the standard range pack).

The Ah rating is what is used as the multiplier for the cell suppliers stated supported values for continuous and peak charge and discharge current, and is typically provided as a C rating. The C value is multiplied by the Ah to provide the current. It's a guess as I don't have the datasheet for the specific cells used in the Mach-e, but the C rating would typically be something like:

1C for continuous charge current
2C for continuous discharge current
5C for peak or impulse discharge current (typically 10 second pulse)

The 72Ah cells likely support the following currents:
Continuous charge current = 72Ah x 1C = 72A
Continuous discharge current = 72Ah x 2C = 144A
Impulse discharge current = 72Ah x 5C = 360A

Again, this is a bit of an educated guess as I don't have the data for these specific cells.

I have been involved with EV battery pack design for over 10 years and have helped in the design of BMS ICs and supported the development of BMS electronics for several OEMs. While I don't have the datasheet for the specific cell used in the Mach-e, I have datasheets for many similar cells.
 
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netsarefun

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My concern with Tesla's 5000 cylinder battery approach is recycling. It seems a whole lot easier to disassemble a pouch cell and extract the rare earths vs having to break thousands of batteries out of a plastic resin to get to them.
doesn’t matter much when recycling is done this way
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