Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register
  • The final cut of the 9th episode of the Tesla Motors Club Podcast, featuring Chad Schwitters, the former president of Plug In America, is now available. You can watch it now on YouTube or listen to it on all major podcast networks.

Battery Voltage difference between models

I have a 2014 S 60 with 50kwh (estimated) usable capacity.

Probably one or 2 of my modules has a dodgy cell in it, but even if that is the case, original capacity is only 58KWH usable? Not very much.

Does the voltage of each pack differ depending on capacity?

As far as I know, each module is about 4.5KWH (assuming no degradation), so I guess the S 60 has 14 modules? And an S 85 has 18 modules?

Since there are more cells in the S 85, does that mean the voltage is higher?

Does anyone know if there is some empty space in the S 60 packs where you can just insert 4 more modules and basically turn the car into an S 85?

Anyone have any experience with this?
 

MP3Mike

Well-Known Member
Feb 1, 2016
18,056
44,490
Oregon
so I guess the S 60 has 14 modules? And an S 85 has 18 modules?

Since there are more cells in the S 85, does that mean the voltage is higher?

Does anyone know if there is some empty space in the S 60 packs where you can just insert 4 more modules and basically turn the car into an S 85?

The original 60kWh pack has 14 modules, with blank/empty cells placed throughout each module. The 85 kWh pack has 16 modules that are fully populated with cells. (The 70 kWh pack has 14 fully populated modules just like the 85 kWh packs.)

No, you can not just add 2 modules to a 60kWh pack to make it a 85kWh pack.

The 60/70 kWh packs are ~350 volts, while the 85/90/100 kWh packs are ~400 volts.
 
  • Informative
Reactions: Rocky_H
The 60/70 kWh packs are ~350 volts

This is interesting. Presumably then you could replace the 60kwh battery pack with a 70kwh battery pack and you don't even need to update the Tesla's computer. If the voltages are the same, it should just charge and discharge normally, but it will just have more power right?

So will the BMU re-calibrate over time to account for the extra capacity?
 

scaesare

Well-Known Member
Mar 14, 2013
8,642
15,405
NoVA
This is interesting. Presumably then you could replace the 60kwh battery pack with a 70kwh battery pack and you don't even need to update the Tesla's computer. If the voltages are the same, it should just charge and discharge normally, but it will just have more power right?

So will the BMU re-calibrate over time to account for the extra capacity?
The car's firmware configuration knows what model it is. Simply swapping packs won't change that, and I suspect there will be some issues there.
 
  • Helpful
Reactions: Rocky_H

apacheguy

S Sig #255
Oct 21, 2012
5,122
1,312
So Cal
This is interesting. Presumably then you could replace the 60kwh battery pack with a 70kwh battery pack and you don't even need to update the Tesla's computer. If the voltages are the same, it should just charge and discharge normally, but it will just have more power right?

So will the BMU re-calibrate over time to account for the extra capacity?

Definitely cannot swap packs without updating the vehicle config.
 

Products we're discussing on TMC...

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top