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I can confirm @wk057’s data, at least my car and have no reason at all based on all about my car he shared to have any doubts. A small snippet of he shared.
If this were gm/Ford etc people would be losing their sh$t. I’m really glad I didn’t “upgrade” to the 90 pack like we were thinking when we purchased. This is bad, like defraud non 60 / 100 buyers. And 90 buyers even worse, I’m at least a stone throw away.
But given the AP2 debacle and this, it’s quite sad to love Tesla....
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Pack lifetime kWh used: 4010 kWh
Pack software energy limit: 72.000 kWh (100%)
Pack software type: Energy75If this were gm/Ford etc people would be losing their sh$t. I’m really glad I didn’t “upgrade” to the 90 pack like we were thinking when we purchased. This is bad, like defraud non 60 / 100 buyers. And 90 buyers even worse, I’m at least a stone throw away.
But given the AP2 debacle and this, it’s quite sad to love Tesla....
You should post them, Tesla is doing this to their customers and customers need to know what’s going on behind the curtain...
FlatSix911
Porsche 918 Hybrid
Time for a trip in the Wayback machine to December 14th, 2016 on Electrek ...
Tesla’s hacked Battery Management System exposes the real usable capacity of its battery packs
Jason Hughes, wk057 a Tesla owner and hacker tinkerer, was the first to reveal the discrepancy in Tesla’s advertised battery capacity versus the actual capacity in the pack and the available capacity. He did it through a tear down of the since discontinued 85 kWh battery pack of a Model S. He found that the 85 KWh battery pack actually only had a capacity of up to 81 kWh and ~77 kWh usable capacity...
Now the data is directly from Tesla’s software and not a calculation based on the capacity of cells from a tear down of a pack. He gathered similar data from other Tesla models. Here’s a list he sent to Electrek:
Tesla’s hacked Battery Management System exposes the real usable capacity of its battery packs
Jason Hughes, wk057 a Tesla owner and hacker tinkerer, was the first to reveal the discrepancy in Tesla’s advertised battery capacity versus the actual capacity in the pack and the available capacity. He did it through a tear down of the since discontinued 85 kWh battery pack of a Model S. He found that the 85 KWh battery pack actually only had a capacity of up to 81 kWh and ~77 kWh usable capacity...
Now the data is directly from Tesla’s software and not a calculation based on the capacity of cells from a tear down of a pack. He gathered similar data from other Tesla models. Here’s a list he sent to Electrek:
- Original 60 – ~61 kWh total capacity, ~58.5 kWh usable.
- 85/P85/85D/P85D – ~81.5 kWh total capacity, ~77.5 kWh usable
- 90D/P90D – ~85.8 kWh total capacity, 81.8 kWh usable
- Original 70 – ~71.2 kWh total capacity, 68.8 kWh usable
- 75/75D – 75 kWh total capacity, 72.6 kWh usable
- Software limited 60/60D – 62.4 kWh usable
- Software limited 70/70D – 65.9 kWh usable
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I would guess around mid June of 2017 when they start producing 75 models with "new drive units" which improves vehicle performance
Interesting conversation here. I had my 85 battery replaced under warranty and it was showing very little degaradation (maybe 4 miles) over three years. They installed a brand new 90 pack that seems to have been built in September 2017 according to the serial number. Until they replaced my pack I wasn’t even aware they were still making new 90 packs. Should I be worried? Hopefully these new 90 packs have the new chemistry.
islandbayy
Active Member
Curious, but maybe they had to to fulfill orders already placed. May I ask, did they software lock the battery or did you basically get a free 90 upgrade?
I heard that they even rebadge the cars and update the software configuration so it shows as a 90kWh car when they replace the battery.
I can confirm it shows as a 90 and they rebadged. Range is now about 20 miles more than the 85 had. I’ll be keeping a close eye on degradation over the next year and hope it stabilizes somewhere close to that of the 85
JRP3
Hyperactive Member
Oh, I'd like to hear this can-of-worms......
@islandbayy What supercharging issues are you seeing? I'm seeing weird rapid tapers within 60 seconds of starting supercharging, tapering down to 90kwh and random capping in the 60kwh range even with less than 30% SOC.
^ That's a whole different can of worms than the capacity issue. Suffice it to say the 90 packs are much more prone to SoC imbalance between cell groups. If one group has over about a 20 mV delta from the pack average, charge speed will taper. The higher the delta, the worse the charge speed reduction.
I swapped out the 90 pack on my S with a newer one because I had two cell groups at something like 40mV delta from the rest of the pack... my top supercharger speed was about 50 kW no matter where I was and it made charging time on my last trip with that pack take 3x as long. The new one is already starting to develop its own uncorrectable imbalance after just ~6000 miles of use.
Suffice it to say... **** the 90 packs.
Failing is the wrong word. More like random, rapid, and extensive degradation (increase in internal resistance) of individual cells causing an uncorrectable imbalance (where the ~100mA bleeder resistors don't have a chance of maintaining balance under normal use).
40 mV is HUGE. The most I ever see my 85 kWh is 6 mV at idle, usually 4 mV. Any idea why the BMS can't keep these 90 kWh packs balanced?
Oh, so certain cells are degrading much faster than other ones in the brick. Weird.
JRP3
Hyperactive Member
That sounds like a quality control issue in the cell manufacturing process as opposed to an inherent flaw in the general cell chemistry.
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