Marstek Venus E Mini 2kWh wall-mounted plug-in battery2kWh LFP plug-in battery with 1.5kW bidirectional inverter, 105mm deep

Overview

Venus E Mini is the 105mm-deep wall-mounted plug-in battery of the Marstek range. It holds 2,009.6Wh in two 314Ah LFP cells, charges with 1.5kVA and returns 800VA or 1.5kVA to the home circuit through its MST-grid port. The backup socket delivers 1.5kVA, with 1.8kVA for 60s and switchover in less than 15ms. Weighing 22kg, it is intended for balconies, garages and other tight spaces; two units with the single-phase SmartBox provide 3kW and 4kWh. Battery-to-AC efficiency exceeds 88%.

• 2,009.6Wh LFP with 314Ah cells, 90% depth of discharge
• 1.5kW charging; 800VA or 1.5kVA output
• 1.5kVA backup, 1.8kVA peak for 60s, 15ms switchover
• 105mm deep, 22kg, wall-mounted
• IP65, -20…+60°C, more than 10,000 cycles
• Two units with SmartBox: 3kW and 4kWh

How it works

Venus E Mini stores energy on the AC side of the home. It plugs into the household circuit through its MST-grid port, charges with up to 1.5kVA from PV surplus or the grid, and returns energy through the same connection, so the existing PV inverter stays untouched whatever its brand. A European socket on the unit supplies selected loads during an outage, switching over in less than 15ms.

The battery uses two 314Ah LFP cells in series (6.4V, 2,009.6Wh) with an integrated BMS that monitors overcharge, overdischarge, overcurrent, overvoltage, short circuit and overtemperature. Marstek rates the cells at more than 10,000 cycles at 25°C, with 80% capacity remaining at that point.

Installation and compatibility

At 386×450×105mm and 22kg, the unit hangs on a wall with heat dissipated through its full rear surface, and Marstek names balconies, garages and outdoor locations as typical sites. It is IP65-rated, naturally cooled and runs from -20 to +60°C up to 2,000m. Two units can be combined with the single-phase SmartBox for whole-home backup of 3kW and 4kWh. Check local rules on plug-in storage and feed-in power before connection.

Operating modes and monitoring

The Marstek app connects over Bluetooth and Wi-Fi and offers manual, self-consumption, AI and UPS modes. Self-consumption and zero export need a meter on the main panel, such as the Marstek CT002 or a supported Shelly meter. The AI mode learns household consumption, takes weather data and electricity prices into account and shifts charging to cheaper hours. The datasheet gives two output ratings, 800VA and 1.5kVA; which one may be used depends on local rules for plug-in devices. LEDs on the front show grid, backup, CT, Wi-Fi and Bluetooth status.

Questions and answers