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Changing Battery in Model S

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I have a 2014 Model S 60.

I'm looking at upgrading my car, and by upgrading, I really mean upgrade the actual car that I'm driving now, rather than getting a new car.

I found a couple of salvage Model X which would cost too much to repair. However, the battery packs look good. I've got my eye on a 2017 Model X 90D. My current car is a 2014 S 60, and it doesn't look I can squeeze any more than 50kwh out of it. If I run from 100% to 0% (so not including the hidden buffer) I'm only getting around 49KWH, which really means my realistic range is only 250km / 150miles.

I'm wondering if the battery pack from the Model X would fit in my Model S, and if it will, if anyone has managed to actually put in a bigger battery from another car into their own car?

Before anyone advises against doing this, know that my car is already out of warranty.

1.) I've driven over 50k miles
2.) My car is now 4 years old
3.) My car is out of zone (US car in Europe)

Since the wheelbase is the same, I assume the packs used between S and X and the same, and so should fit nicely. If so, then a simple software update (obviously not an OTA one) to account for the extra battery capacity, and that should do it?

I figure even if the 90kwh battery pack only had a usable capacity of 743KwH, that would give me 365km of very comfortable driving, or 400km of rated range.

Anyone have any experience in this area?
 
I am no expert, but the battery configurations are a lot different from one another.

I would advise against it as well, as the connectors for the higher battery pack might be slightly bigger than the one currently on your model S. The model X draws more electricity than the normal batteries on the model s, thus the electrical components may slightly differ from one another. I also do not believe Tesla would change your system configurations to allow such a change. They will eventually not touch your Tesla anymore, since you have altered the software / hardware components.
 
There are folks here on the forums that know the answer to this. I look forward to their insight. Looking at the S75D with the BTX8 (P85D) battery, it appears you get the S75D torque, max power in between S75D and S100D (but nowhere near P85D), little and late Back EMF like the high voltage P85, but directly to your question a software limited battery.

I think it will work. Heck, you can buy battery replacement services on eBay.
 
I am no expert, but the battery configurations are a lot different from one another.

I would advise against it as well, as the connectors for the higher battery pack might be slightly bigger than the one currently on your model S. The model X draws more electricity than the normal batteries on the model s, thus the electrical components may slightly differ from one another. I also do not believe Tesla would change your system configurations to allow such a change. They will eventually not touch your Tesla anymore, since you have altered the software / hardware components.

It's a fair point. My current car is NOT a salvage car, and everything is all good with Tesla if I needed to get some work done officially. I've only had some minor body work done outside of official Tesla approved body shops.

Still... my battery is a real problem for me for long distance drives, and being my car is out of region, it would cost me a fair bit just to get the car to a Tesla Service Centre. So any problems I have actually need to be pretty significant for me to want to do that. My battery is still technically under warranty for another 4 years, but they claim that my approximately 15% degradation is not significant enough to claim on warranty. And if I wanted to send the car back to the US, it would probably cost me at least $4,000 round trip.

I could buy salvaged cars for around $20k (+ tax + shipping), get the battery and sell the rest for scrap. Half the Teslas driving around where I live are salvage, so there are people here who do all the 'servicing' and repairs. I'm starting to wonder if keeping my car squeeky clean in the eyes of Tesla is really worth while.
 
So if it wouldn't ruin the battery I would have been thinking about adding two battery modules to make a Frankenstein, but still degraded, 75 as the cheapest way to get back to 60kWh. Your pack should have 12 modules. 13 and 14 should be empty. But Jason Hughes (wk057) says that unbalancing the pack will destroy the battery, so it probably isn't as simple as finding similarly aged cells that match the cell degradation, hooking them up to the electrical and cooling loops and plugging it back in. But if you could, having a 400v battery would be some performance boost for later cars, since your car would at least pickup some high speed passing benefits (lower back EMF).

The car is designed to change batteries easily. For a while Tesla thought you would do that at supercharging stations when you travelled. So it seems a shame to void your warranty.

I would contact the eBay sellers of replacement batteries and see if they could ship you a battery to have it installed locally. If they don't have to root the car in order to get it to charge to full that is great news. There is some chance that the car will software limit a bigger battery to the original range and original max power settings. The BTX8 battery, for example, in some non US S75Ds is 85kWh and cannot be unlocked to date. It still may be cheaper to buy local salvage batteries, but asking them may be an easy way to verify what is possible.

If you have to root the car, I would go for the "Full Monte" and change the torque settings, max power and the full battery capacity. I think safest max power limit will be determined by the fuse and wiring harness combo on your car,
 
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I have a 2014 Model S 60.

I'm looking at upgrading my car, and by upgrading, I really mean upgrade the actual car that I'm driving now, rather than getting a new car.

I found a couple of salvage Model X which would cost too much to repair. However, the battery packs look good. I've got my eye on a 2017 Model X 90D. My current car is a 2014 S 60, and it doesn't look I can squeeze any more than 50kwh out of it. If I run from 100% to 0% (so not including the hidden buffer) I'm only getting around 49KWH, which really means my realistic range is only 250km / 150miles.

I'm wondering if the battery pack from the Model X would fit in my Model S, and if it will, if anyone has managed to actually put in a bigger battery from another car into their own car?

Before anyone advises against doing this, know that my car is already out of warranty.

1.) I've driven over 50k miles
2.) My car is now 4 years old
3.) My car is out of zone (US car in Europe)

Since the wheelbase is the same, I assume the packs used between S and X and the same, and so should fit nicely. If so, then a simple software update (obviously not an OTA one) to account for the extra battery capacity, and that should do it?

I figure even if the 90kwh battery pack only had a usable capacity of 743KwH, that would give me 365km of very comfortable driving, or 400km of rated range.

Anyone have any experience in this area?