Marstek VENUS E Mini
A 2 kWh LFP wall battery, only 105 mm thin and 22 kg, with a 1.5 kW bidirectional inverter and 1.5 kW backup, expandable to two units with the SmartBox.
- Best for compact backup
- AC battery
- 2 kWh
- 1.5 kW output
- Made by Marstek.
- Capacity: 2 kWh per unit, with LFP cells rated for over 10,000 deep cycles.
- Power: 1.5 kW bidirectional on-grid inverter and 1.5 kW backup (1.8 kW peak) with a switchover under 15 ms.
- Expandable to two units with the single-phase SmartBox: 3 kW and 4 kWh.
- Rules: whether you can use it as a plug-in battery depends on your country.
Not tested by us
We have not tested the Marstek VENUS E Mini. The figures on this page come from the sources listed at the end of the page, checked on 12 November 2026, and we do not show prices. "Best for" is based on what the maker says the product is designed for, not on our own tests.
Key figures
2 kWh
Capacity per unit
1.5 kW
Bidirectional power
22 kg
Weight (Marstek)
Specifications
Last checked on 12 November 2026. The grey text under each name explains what the value means. To see it next to other products, compare it in our comparison tool.
| Specification | Value |
|---|---|
| Storage | |
| CapacityHow much energy the battery stores. Bigger means longer runtime or more of your own solar power used later. | 2 kWh per unit |
| Battery chemistryLFP (lithium iron phosphate) cells are known for long life and stable behaviour with heat. | Lithium iron phosphate (LFP) |
| Cycle lifeHow many full charge and discharge cycles the cells are rated for before they hold less than the stated share of their original capacity. | Over 10,000 deep cycles and a design life of 15 years |
| ExpansionExtra battery units that add storage to the same system. | Up to two units with the single-phase SmartBox, for 3 kW and 4 kWh |
| Power | |
| AC output, grid-connectedThe lower output allowed when it feeds power into the home's circuits or the grid. | 1.5 kW bidirectional on-grid inverter |
| Backup outputA separate socket that keeps selected devices running when the grid is down. | 1.5 kW continuous, 1.8 kW peak, switchover under 15 ms (EPS) |
| AC charging inputHow fast it charges from a wall socket or the grid. | Not stated in the sources we read |
| Efficiency and standby useLosses when charging, discharging and doing nothing. | Not stated in the sources we read |
| Solar | |
| Solar inputHow much solar panel power it accepts. A higher figure fills the battery faster on a sunny day. | Not stated in the sources we read |
| Grid connectionThe supply type it is built for. Check it matches your home's supply. | AC-coupled: plugs into the home grid and works with any existing solar system; Marstek says installation takes under 5 minutes |
| Solar and off-grid | |
| Works with solar panelsWhether you can charge it from solar panels. Yes means a built-in solar input or a compatible solar setup; read the detail for the voltage and power limits. | Yes: AC-coupled, works with any existing solar system; no solar input of its own on the pages we read. |
| Off-grid useWhether the maker describes it running with no grid connection at all, for example in a cabin, van or off-grid home. Backup only means it covers power cuts but needs the grid the rest of the time. | Partly: 1.5 kW backup output (switchover under 15 ms) in a power cut; Marstek describes a grid-connected system. |
| Connection and housing | |
| Dimensions (W × D × H)Check the space before you buy, including room around it for airflow and cables. | Only the thickness is stated: 105 mm. Other dimensions not stated in the sources we read |
| WeightMatters for lifting, wall mounting and moving it. | 22 kg |
| Protection ratingIP ratings show protection from dust and water. IP55 and IP65 are rated for outdoor-style exposure; check the installation guidance. | IP65 |
| Operating temperatureThe range it is rated to work in. Cold and heat can reduce performance. | -20 to 60 °C |
| Noise levelFan noise while working. | Not stated in the sources we read |
| ConnectivityHow you monitor and control it, usually through an app. | Marstek app with manual, self-consumption and AI-optimised modes |
| Warranty | |
| WarrantyThe period the maker covers. Read the terms: conditions and capacity guarantees differ. | Not stated in the sources we read |
Compatible with
What Marstek says this product works with. Anything not listed here is not confirmed.
- Solar systems
- Marstek says it works independently of your solar inverter brand or protocol.
- Expansion
- Up to two units with the single-phase Marstek SmartBox.
Rules where you live
Rules for plug-in batteries differ by country. In Great Britain, plug-in solar kits of up to 800 VA have been legal since 27 August 2026, but the rules exclude plug-in batteries.
Check the rules, incentives and tariffs for your own country in our country guides.
Strengths and things to check
Strengths
- Only 105 mm thin and 22 kg
- 1.5 kW bidirectional power and 1.5 kW backup
- Over 10,000 deep cycles per Marstek
- IP65 for indoor and outdoor use
- Expandable to 4 kWh with the SmartBox
Worth checking before you buy
- Whether it counts as a plug-in product depends on your country: check the rules below
- Full dimensions, efficiency, noise and warranty are not on Marstek's product page
- Marstek does not state a solar input on the page we read
- Expansion needs the separate SmartBox
Change log
We record changes to this page here, so you can see when figures such as the warranty were last updated.
- 12 November 2026
- Page published. Warranty at publication: not stated on the Marstek product page. This page covers the VENUS E Mini, not the VENUS E 4.0 or VENUS E 3.0.
- 12 November 2026
- Added the Solar and off-grid specifications (solar panels and off-grid use).
Where this information comes from
We have not tested the VENUS E Mini. Every figure above comes from Marstek's VENUS E Mini product page, last checked on 12 November 2026. A value this page does not state is shown as not stated.
We do not show prices, because they change often and differ between sellers.
- Manufacturer Marstek VENUS E Mini product page
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Common questions about Marstek VENUS E Mini
Can I use the Marstek VENUS E Mini as a plug-in battery in my country?
It depends on local rules. In Great Britain, plug-in solar kits up to 800 VA are legal since 27 August 2026 but the rules exclude plug-in batteries. Check our country guides.
How big is the Marstek VENUS E Mini?
Marstek states 105 mm thickness and 22 kg. It does not give the other dimensions on the product page.
How far can the VENUS E Mini be expanded?
Marstek says up to two units with the single-phase SmartBox, for 3 kW and 4 kWh.
Related guides
How much could a battery save you?
Our calculator uses your own usage and tariff to estimate what a home battery could save, with conservative assumptions.