55 kWh or 60 kWh battery?

[m555]

I got battery replacement on my TM3 SR+MIC 2021 LFP in warranty due to isolation failures (waited 3 month for the battery to arrive). They confirmed I got a new battery, I can see in SMT that it has almost zero AC/DC Charge Total. I'm not sure if they manufactured a new 55 kWh battery for me (AFAIK 55 kWH LFP is not being used in new cars anymore) or gave me 60 kWh and software-locked it.

I have an old screenshot of ScanMyTesla showing "Nominal full pack" of 52.3 kWh and "Energy buffer" of 2.35 kWh. "Full Pack when new" was 55.1 kWh. With the replaced battery I saw "Nominal full pack" 55.0 kWh, "Energy buffer" 5.75 kWh, full pack when new same as before (55.1). After a week, nominal full pack is little lower (54.7), but energy buffer got higher, first about 5.8 kWh and today 6.00 kWh.

I have found in some other thread info that the Energy buffer indeed can change based on how BMS is confused. Do you think so big buffer is just result of new battery (with BMS still calibrating - I just full charged only maybe 5x since the replacement) or can be indication of bigger battery capacity?
How does software-locking capacity work? Do they limit max charge (so 100% is in fact maybe 95%), or max discharge (so 0% is in fact ~5%)?
I have the info from invoice ASY,HVBAT,E1 PRIS,RWD,3PH (1567439-00-A), but google nor EPC Tesla knows anything about it.

 

[AlanSubie4Life]

I got battery replacement on my TM3 SR+MIC 2021 LFP in warranty due to isolation failures (waited 3 month for the battery to arrive). They confirmed I got a new battery, I can see in SMT that it has almost zero AC/DC Charge Total. I'm not sure if they manufactured a new 55 kWh battery for me (AFAIK 55 kWH LFP is not being used in new cars anymore) or gave me 60 kWh and software-locked it.

I have an old screenshot of ScanMyTesla showing "Nominal full pack" of 52.3 kWh and "Energy buffer" of 2.35 kWh. "Full Pack when new" was 55.1 kWh. With the replaced battery I saw "Nominal full pack" 55.0 kWh, "Energy buffer" 5.75 kWh, full pack when new same as before (55.1). After a week, nominal full pack is little lower (54.7), but energy buffer got higher, first about 5.8 kWh and today 6.00 kWh.

I have found in some other thread info that the Energy buffer indeed can change based on how BMS is confused. Do you think so big buffer is just result of new battery (with BMS still calibrating - I just full charged only maybe 5x since the replacement) or can be indication of bigger battery capacity?
How does software-locking capacity work? Do they limit max charge (so 100% is in fact maybe 95%), or max discharge (so 0% is in fact ~5%)?
I have the info from invoice ASY,HVBAT,E1 PRIS,RWD,3PH (1567439-00-A), but google nor EPC Tesla knows anything about it.

Great that you got a new battery.

It’s probably 55kWh but it would be hard to tell since regen is not as limited on LFPs. Capacity limits are done with a top lock so regen is not as limited at the top.

Energy buffer being so large is just a function of LFP BMS confusion probably. Just do a couple of deeper cycles and charge to 100%. It may even be something that is only there at the beginning of battery life and Tesla phases it out as the BMS gets a better estimate (but 100% charge likely important too).

 

[STS-134]

Great that you got a new battery.

It’s probably 55kWh but it would be hard to tell since regen is not as limited on LFPs. Capacity limits are done with a top lock so regen is not as limited at the top.

Can you even do that with LFP? If the top isn't really the top, it would be in the very flat part of the SoC/voltage curve and the BMS would lose track of where it was. Software locking the bottom seems even more strange though, as there could be energy left in there that you could use in an emergency that it's just refusing to consume.

 

[AlanSubie4Life]

Can you even do that with LFP? If the top isn't really the top, it would be in the very flat part of the SoC/voltage curve and the BMS would lose track of where it was. Software locking the bottom seems even more strange though, as there could be energy left in there that you could use in an emergency that it's just refusing to consume.

Good point. Yeah, seems very likely to just be a new 55kWh. They won’t do special software just for a few people with battery failures. Making batteries is not hard!