Model 3/Y 54 and 75 kWh (pre-facelift, before 2021): imbalance happens, but less often
Based on field experience, 54/75 kWh pre-facelift packs show fewer cases of chronic imbalance than 82 kWh Panasonic. Even so, check balance logs, equalization speed at 100%, and temperature.
⚠️ Don't confuse: the "54" pre-facelift (stable) vs the SR 55 kWh 2021 (Panasonic 1L)
This article is about the pre-facelift packs of 2019–2020 (Panasonic "1", older-generation 2170 cells), which really are calmer. The Standard Range ~55 kWh from early 2021 is a different pack: Panasonic "1L" on the problematic L-chemistry, a relative of the 82 kWh (2170L). It also drifts into imbalance often (BMS_a066/a064/a079), and it was built for only a short time (until the 2021 switch to LFP), so donor modules are harder to find at salvage yards than for the 82.
- Codes and costs breakdown: Tesla battery errors (BMS).
- Close case: 82 kWh Panasonic imbalance.
Link
- Model 3/Y battery lineup context: https://tff-forum.de/t/model-3-82-kwh-netto-brutto/118853
Sources
- https://tff-forum.de/t/model-3-82-kwh-netto-brutto/118853
Related
Full list →Model 3/Y 82 kWh Panasonic (US): frequent module imbalance
American 2021–2022 LR cars show frequent imbalances; the root cause is current leaks through the fuse-wire "fingers" of the 21700 cells. Thresholds (up to 8 mV is fine, alert at >150 mV), a breakdown of the BMS_a029/a064/a074/a079 codes from Toolbox, photos of leaking modules and every treatment option, from module repair (tsk.by's recommendation) to a swap to LG 79.
Model 3/Y: HV battery module-level repair, who can do it in Belarus and what it costs
A Model 3/Y pack has 4 modules; one weak module causes imbalance errors. A module swap runs $1,300-2,200 plus shipping in Minsk vs $12,000+ for a new pack.
Tesla Model 3/Y LFP 60–64 kWh (CATL/BYD): durably reliable, but RWD only
LFP batteries (CATL/BYD) are a good choice for long-term ownership: low degradation with daily 80–100% charging and simple operation. Usually fitted to RWD.
Model 3/Y 79 kWh LG (Europe, NOT China): a reliable choice
LG 79 kWh (EU) shows the lowest failure rate per field reports. A good balance of longevity and charge.