Tesla Model 3 Battery with SolaX Inverter

Pairing a used Tesla Model 3 or Model Y HV pack with a SolaX X3 Hybrid G4 HV inverter for residential and small commercial energy storage.

Direct answer. A complete Tesla Model 3 or Model Y HV pack (50, 60, 75 or 82 kWh, nominal 350–410 V DC) is compatible with the SolaX X3 Hybrid G4 High-Voltage series (X3-Hybrid-5.0-HV through X3-Hybrid-15.0-HV, DC input 90–800 V). The BMS-EV controller sits on the vehicle CAN bus, reads the factory BMS, and re-encodes the data as Pylontech HV battery frames, which the SolaX firmware natively supports. For 15–30 kW three-phase installations use the X3-Ultra Hybrid instead — same protocol, higher power rating.

What works

ComponentStatusNotes
Tesla Model 3 SR / LR / Performance packYesNCA and LFP cell chemistries both supported
Tesla Model Y LR / Performance packYesIdentical BMS to Model 3
SolaX X3 Hybrid G4 HV (5–15 kW)YesPylontech HV protocol on inverter CAN port
SolaX X3-Ultra HybridYes15–30 kW three-phase, same protocol
SolaX X1 Boost / Mini (string only)NoNo battery interface
SolaX X3 Hybrid G4 LV variantNo48 V nominal, incompatible with HV pack

Supported SolaX inverter models

ModelAC powerPhaseDC battery rangeMPPT
X3-Hybrid-5.0-HV5.0 kW3-phase90–800 V2
X3-Hybrid-6.0-HV6.0 kW3-phase90–800 V2
X3-Hybrid-8.0-HV8.0 kW3-phase90–800 V2
X3-Hybrid-10.0-HV10.0 kW3-phase90–800 V2
X3-Hybrid-12.0-HV12.0 kW3-phase90–800 V2
X3-Hybrid-15.0-HV15.0 kW3-phase90–800 V2
X3-Ultra-15K15.0 kW3-phase180–800 V3
X3-Ultra-19.9K19.9 kW3-phase180–800 V3
X3-Ultra-25K25.0 kW3-phase180–800 V3
X3-Ultra-30K30.0 kW3-phase180–800 V3

Battery voltage range match

The Tesla Model 3 / Y HV pack has a nominal voltage of approximately 350–410 V DC (depending on state of charge). Full pack range is roughly 300 V (empty, 0% SoC cutoff) to 415 V (100% SoC, freshly charged NCA). The LFP variant operates at 320–398 V.

The SolaX X3 Hybrid G4 HV accepts battery voltages from 90 V to 800 V. The Tesla operating window sits comfortably in the middle of that range, so no voltage adaptation is required — the BMS-EV controller simply reports the true pack voltage on the CAN bus and the SolaX MPPT-linked battery converter tracks it.

CAN protocol mapping

SolaX X3 Hybrid firmware natively supports the Pylontech HV battery protocol on its RJ45 CAN port. The BMS-EV controller performs the translation:

DataSource (Tesla BMS)Target (Pylontech HV frame)
Pack voltage0x132 byte 0–10x4210 byte 0–1
Pack current0x132 byte 2–30x4210 byte 2–3
SoC0x33A byte 50x4210 byte 4
Max cell temperature0x312 byte 30x4220 byte 4
Charge current limitComputed from BMS + SoC0x4230 byte 2–3
Discharge current limitComputed from BMS + SoC0x4230 byte 4–5
Alarm flags0x321 bit-mapped0x4240 byte 0–3

Wiring architecture

┌────────────────┐ ┌───────────────┐ ┌────────────────┐ │ Tesla Model 3 │ │ BMS-EV │ │ SolaX X3 │ │ HV pack │ │ Controller │ │ Hybrid G4 HV │ │ │ │ │ │ │ │ 350-410 V DC │───────►│ Pylontech │───────►│ Battery port │ │ │ CAN │ HV emulator │ CAN │ 90-800 V DC │ │ Factory BMS │ 500k │ │ 500k │ │ └────────┬───────┘ └───────┬───────┘ └────────┬───────┘ │ │ │ │ HV DC bus (contactors + precharge in pack) │ └──────────────────────────────────────────────────┘ │ ▼ ┌──────────────────┐ │ Grid + AC loads │ │ (3-phase) │ └──────────────────┘

Installation requirements

Engineering values below are examples. Final conductor cross-section and protective-device sizing must be calculated for the actual pack, maximum current, cable length, installation method, ambient temperature and applicable local standards (IEC 60364-7-712, VDE-AR-N 4105, NEC 690).

Known limitations

FAQ

Can I use a Tesla Model S or Model X pack with the same setup?

Model S and Model X packs use a similar HV architecture (~360–400 V nominal) but have a different BMS communication protocol. A dedicated BMS-EV firmware build is required — the controller hardware is the same, but the vehicle-side firmware must be Tesla S/X, not Tesla Model 3/Y.

Does this work with the LFP variant of the Model 3?

Yes. The LFP Standard Range Plus pack (~55 kWh usable, 320–398 V) works with the same BMS-EV controller. The Pylontech HV frames report the true chemistry-dependent voltage and current limits, so the SolaX inverter adapts its charge profile automatically.

Can I connect two Tesla packs in parallel to one X3-Ultra inverter?

Not directly. Two packs at slightly different SoC will exchange large currents through their contactors. If parallel operation is required, each pack must have its own BMS-EV controller and the inverter must be configured for two independent battery banks — the X3-Ultra supports up to two BAT ports for this.

What happens if the SolaX inverter loses CAN communication with the battery?

The X3 Hybrid firmware treats missing battery telemetry as a fault after ~30 seconds and opens its internal battery contactors. No damage occurs, but the inverter will not restart until CAN traffic resumes. The BMS-EV controller has a watchdog that reboots the CAN stack if the vehicle BMS stops responding.

Do I need to keep the Tesla pack's original contactors?

Yes. The main positive and negative contactors and the precharge resistor inside the Tesla pack are used as-is. The BMS-EV controller drives them via the pack's original service connector wiring. Do not remove or bypass them.

Will the SolaX inverter perform emergency backup with a Tesla pack?

Yes, if the installation includes the SolaX X3-Matebox or an equivalent EPS (Emergency Power Supply) switch. Backup power output is limited to the inverter's continuous EPS rating (typically 60–80 % of nominal AC power).

Is Pylontech HV really the same as SolaX native HV?

SolaX firmware historically shipped support for BYD, LG Chem and Pylontech HV protocols selectable in the installer menu. Pylontech HV is the most stable option across firmware revisions and is what the BMS-EV controller emulates by default. If the installer accidentally selects "SolaX native" in the menu, the battery will not be detected — reselect "Pylontech" and reboot.

Order a Tesla + SolaX controller
Pre-configured for your exact pack variant and inverter model
Last updated: 2026-09-18
Current firmware: 15.0.14
Technical author: BMS-EV engineering team (Clima Boost sp. z o.o., Poland)
Reviewer: Jakub Lipiński, founder/lead engineer BMS-EV
Revision: 2026-09-18 — aligned with firmware 15.0.14, SOFAR 180–800 V DC verification, Kia EV6 + SOFAR HYD 15KTL case study reference
Related: Tesla Model 3 battery · Compatibility Matrix · Safety