What precautions should I take before installing/adding Stackable Micro Battery?

When installing/adding expansion batteries, it is necessary to power off and shut down the system to protect yourself and the machine. Performing this operation while powered on is not covered under warranty. Please follow the steps below for proper installation: a. Disconnect the Micro Storage Unit and the solar panels. b. Press the on/off button for 2 seconds to turn off the power. c. After turning off the Micro Storage Unit, install the expansion batteries to the Micro Storage Unit. d. Connect solar panels for normal use.

Are there any other precautions that need to be taken when installing and using the product?

Ensure that the AC outlet is properly grounded.

Can I change the battery to the Micro Storage Battery or Stackable Micro Battery by myself?

No. If your battery in Micro Storage Unit or Stackable Micro Battery does not work or working conditions do not meet expectations, please contact the TSUN customer service team for further help.

How to make sure the equipment is safely grounded?

The included AC end cable already ensures that the machine is safely grounded, so there's no need to worry.

Are microinverters required to use Micro Storage Unit?

Micro Storage Unit does not require a microinverter. A microinverter is already incorporated into its all-in-one design that also includes a photovoltaic controller and energy storage battery pack.

Can the Micro Storage Unit charge batteries using the household power grid?

Yes, the Micro Storage Unit can charge your batteries using your home's AC power. It can be scheduled to do so during off-peak hours to reduce costs, and will also automatically charge AC power when the batteries are low and there is insufficient solar power, preventing battery damage and ensuring that you have some reserve energy available.

How do I use Micro Storage Unit to achieve zero-power function?

You need to buy our optional accessory smart meter, which prevents energy back-flow to the public grid by adjusting the output power of the Micro Storage Unit, matching household load in real-time. This achieves the purpose of not transmitting energy to the public grid, which is the anti-back-flow function.

How does the smart meter help Micro Storage Unit achieve zero energy waste?

The smart meter detects the total household electricity consumption, which lets Micro Storage Unit continually adjust output power. It's real-time and precise electrical discharge for your home, helping you achieve efficient energy use without waste.

PowerTrunk (Micro AC Coupled Unit)

MAU4000Elite 4-20 kWh

The MAU4000Elite are versatile AC-coupled energy storage systems, perfect for upgrading existing grid-tied setups or powering new microinverter-based installations. They empower homeowners to slash electricity bills by maximizing self-consumption and intelligently shifting energy use during high-tariff periods.
Designed to grow with your needs, these units support flexible parallel expansion for both single-phase and three-phase systems. At their heart are durable 314Ah high-cycle cells paired with TSUN’s proprietary Battery Optimizer technology. This unique feature allows you to mix existing and new battery modules without performance loss—eliminating traditional matching issues while ensuring long-term safety and peak efficiency.

DATASHEET

Products Storage System Micro Storage System PowerTrunk (Micro AC Coupled Unit)

PowerTrunk AC-Coupled Solar Energy Storage System for Retrofit

MAU4000Elite

Seamlessly Upgrade Your Existing Solar

• AC-Coupled: No inverter replacement. 100% compatible.
• 24/7 Power: Store excess daytime energy for night. Bypass peak rates.
• Extreme Durability: IP65 sealed. Survives monsoon rains and coastal salt mist.

Official MAU4000Elite Home Solar Retrofit System Setup

100% Compatible Retrofit

Advanced AC-Coupled design connects seamlessly with your existing microinverters. Capture excess solar without changing your setup.

Scalable Storage Strategy

Stackable LFP battery modules grow perfectly with your power demands, expanding effortlessly from a baseline of 4kWh up to 20kWh.

Official Residential Solar Energy Storage Application Scene

Balcony Solar Storage Solution - Compact & Powerful

Your Compact Balcony Power Plant

Optimized for balcony space.
Connects directly with grid. Zero rewiring required.

Advanced IP65 weatherproofing for coastal humidity & heavy rainfall.

The Ultimate Plug-and-Play Balcony Solar Battery Storage

Designed specifically for modern apartment living, the MAU4000Elite is a compact LiFePO4 battery for apartment balconies that seamlessly integrates with your setup. If you are looking into retrofitting balcony solar with battery storage, this AC-coupled battery for existing microinverters requires absolutely zero rewiring. It’s the easiest DIY balcony solar storage solution to capture excess daytime power, helping you reduce electricity bills with balcony solar and achieve true energy independence without the complexity of traditional rooftop installations.

The Best Grid-Tied Solar Battery Upgrade for Apartments | 24/7 Smart Power

Official MAU4000Elite Balcony Battery Installation Scene

Existing Solar System? Stop Wasting Your Excess Power.

The PowerTrunk MAU4000Elite series is the ultimate AC-coupled solution designed specifically for households that already have grid-tied solar or balcony microinverter systems. By utilizing innovative AC Coupling technology, it allows you to easily add storage and capture surplus daytime energy for nighttime use, maximizing self-consumption and ROI without complex rewiring.

Zero Rewiring — 100% Compatible with All Grid-Tied Inverters & PV Modules

Mix Old & New Batteries Freely

Our advanced built-in Energy Optimizer allows you to seamlessly mix old and new battery packs. Expand your capacity anytime in the future without suffering from "bucket effect" degradation.

BMS Energy Optimizer technology for mixing old and new LiFePO4 battery modules

Plug and Play Solar Storage Setup - No professional electrician required

Weatherproofed for Extreme Conditions

IP65 Waterproof and Anti-Corrosion Balcony Solar Battery

Engineered for uninterrupted power in uncovered balconies, rooftops, or gardens facing heavy monsoon rains, extreme humidity, or temperature swings (-20°C to 55°C).

Official Automotive-Grade LiFePO4 Battery Cell Technology

High capacity stored power solar unit and specifications

Max Performance

Scalable up to 20kWh: Optimized for high-efficiency energy harvesting and long-term stability with 10,000-cycle design life.

10,000

Life Cycles

2500 W

Max. AC Input

4 kWh

Battery per Unit

20 kWh

Max. Capacity

Max Performance

Scalable up to 20kWh:
Optimized for high-efficiency energy harvesting and long-term stability with 10,000-cycle design life.

10,000

Life Cycles

2500 W

Max. AC Input

4 kWh

Battery per Unit

20 kWh

Max. Capacity

Official PowerTrunk Detail Application Scene in Garden

Official Home Energy Storage Solution System Overview Diagram

Smart Control: Maximum Profit, Zero Headaches

Strict "Zero-Export" Compliance

Bypass tedious utility export approvals. Pairs instantly with Smart Meters to block unauthorized grid feed-in. 100% of your solar yield stays trapped for local use, driving your bills to the absolute minimum.

TOU Arbitrage & Remote Diagnostics

Users: Put savings on autopilot. Schedule discharges via App to beat peak Time-of-Use (TOU) rates.
Installers: Built-in WiFi/Bluetooth enables swift 1-minute commissioning and remote fleet troubleshooting, drastically reducing on-site truck rolls.

Official AI Energy Management Chip architecture

Technical Specifications

Official PowerTrunk Elite Front View specification diagram

Download Datasheet ▼

MAU Elite Datasheet (PDF)

Model	MAU4000Elite
System Type	AC-Coupled Storage
Battery Type	LiFePO4 (LFP)
Capacity (kWh)	4
Max. System Capacity	20 kWh
Life Cycle	10,000 (@25°C)
Max. Output Power [W]	2000
Max. Input Power [W]	2500
Dimensions (mm)	583 × 333 × 375
IP Rating	IP65
Temp. Range	-20°C to 55°C

*Only partial parameters are listed. For the complete specification list, please refer to the official datasheet.

Frequently Asked Questions

What precautions should I take before installing/adding Stackable Micro Battery?

A :

When installing/adding expansion batteries, it is necessary to power off and shut down the system to protect yourself and the machine. Performing this operation while powered on is not covered under warranty. Please follow the steps below for proper installation: a. Disconnect the Micro Storage Unit and the solar panels. b. Press the on/off button for 2 seconds to turn off the power. c. After turning off the Micro Storage Unit, install the expansion batteries to the Micro Storage Unit. d. Connect solar panels for normal use.
Are there any other precautions that need to be taken when installing and using the product?

A :

Ensure that the AC outlet is properly grounded.
Can I change the battery to the Micro Storage Battery or Stackable Micro Battery by myself?

A :

No. If your battery in Micro Storage Unit or Stackable Micro Battery does not work or working conditions do not meet expectations, please contact the TSUN customer service team for further help.
How to make sure the equipment is safely grounded?

A :

The included AC end cable already ensures that the machine is safely grounded, so there's no need to worry.
Are microinverters required to use Micro Storage Unit?

A :

Micro Storage Unit does not require a microinverter. A microinverter is already incorporated into its all-in-one design that also includes a photovoltaic controller and energy storage battery pack.
Can the Micro Storage Unit charge batteries using the household power grid?

A :

Yes, the Micro Storage Unit can charge your batteries using your home's AC power. It can be scheduled to do so during off-peak hours to reduce costs, and will also automatically charge AC power when the batteries are low and there is insufficient solar power, preventing battery damage and ensuring that you have some reserve energy available.
How do I use Micro Storage Unit to achieve zero-power function?

A :

You need to buy our optional accessory smart meter, which prevents energy back-flow to the public grid by adjusting the output power of the Micro Storage Unit, matching household load in real-time. This achieves the purpose of not transmitting energy to the public grid, which is the anti-back-flow function.
How does the smart meter help Micro Storage Unit achieve zero energy waste?

A :

The smart meter detects the total household electricity consumption, which lets Micro Storage Unit continually adjust output power. It's real-time and precise electrical discharge for your home, helping you achieve efficient energy use without waste.