Tesla Energy | Powerwall 3 | 13.5 kWh expansion battery

Tesla Powerwall 3 Expansion – Add 13.5 kWh Capacity to Any Powerwall 3 System

#4: TESLA-1807000-20-B

Tesla Powerwall 3 Expansion Data Sheet

Tesla Powerwall 3 Expansion Mounting Configurations 

Tesla Powerwall 3 Installation Manual

Tesla Powerwall Warranty

Tesla Powerwall 3 Quick Guide Expansion Multi Unit Installation

Tesla Powerwall 3 Quick Guide Required Additional Parts and Tools

Tesla Powerwall 3 Install System Shutdown Switch

The Tesla Powerwall 3 Expansion is the fastest and simplest way to increase storage capacity on an existing Powerwall 3 installation. Each expansion unit adds 13.5 kWh of usable energy without requiring additional inverters, breakers, design revisions, or complex commissioning steps. Installers simply connect the parallel harness, mount the cabinet, and the system automatically synchronises—no firmware flashing or recalculation needed.

Effortless Capacity Scaling

Plug-and-Play Integration

Designed to extend any Powerwall 3 setup, the expansion module instantly syncs with the base battery for seamless operation.

Scalable Architecture

• Add up to 3 expansion batteries to a single Powerwall 3

• Expand total storage to up to 54 kWh
  Ideal for homes with rising energy needs or small-commercial applications.

Engineered for Reliable UK Installation

Indoor & Outdoor Rated

The Powerwall 3 Expansion uses a robust IP67 / NEMA 3R enclosure engineered to withstand:

• Operating temperatures from –20 °C to 50 °C

• Up to 100% humidity
  Perfect for installation in plant rooms, meter cupboards, garages, and external walls throughout the UK.

Slim, Space-Efficient Design

• Cabinet size: 1105 × 609 × 168 mm

• Can be stacked behind the primary Powerwall 3 or mounted alongside it

• Floor or wall mounting supported

  • Wall mounting requires a glass door enclosure

Rapid, Installer-Friendly Setup

Pre-Terminated Parallel Harness

Tesla’s pre-wired harness enables fast connection with minimal tools or wiring complexity.

Auto-Recognition & Balancing

The Tesla QR-code commissioning wizard:

• Detects serial numbers automatically

• Balances pack voltages

• Syncs expansion units with the existing Powerwall 3 system
  All within minutes.

Unified Tesla Ecosystem

All monitoring, firmware updates, alerts and performance data remain within the Tesla App, reducing support calls and ensuring a smooth customer experience.

Technical Specifications

Battery Performance

• Nominal energy per unit: 13.5 kWh

• Weight: 118.5 kg

• System compatibility: Tesla Powerwall 3 only

Certifications

Fully compliant with international safety and performance standards:

• UL 1973

• UL 9540

• Pollution Degree 3
  Trusted by insurers and UK DNOs.

Mounting Options

• Floor mount (standard)

• Wall mount (requires glass door enclosure)