Einhell 4–6 Ah Plus Battery – 18 V Multi Ah Power Battery

The Einhell 4–6 Ah Plus Battery is part of the Power X-Change system. It offers seamless compatibility with all 18 V cordless tools, submersible pumps and the Flux FBM 4100 battery motor for drum pumps.

Switchable power mode means you only need one rechargeable battery solution for every item, saving cost and also providing true flexibility. In addition, universal compatibility not only streamlines your toolkit, but also helps protect the environment by cutting down on waste.

• 4 Ah mode for up to 300% longer battery life
• 6 Ah mode for maximum runtime and performance

Ideal for routine garden tasks and high-demand tools such as pumps, its advanced lithium-ion cells deliver 100% more power and maintain strong output even under heavy load, whilst PLUS technology provides an extra boost for energy-intensive work.

Furthermore, the rechargeable battery resists memory effect and low self-discharge ensures consistently high power and long-lasting charge retention.

Einhell battery – durable, intelligent and built for long service life

With an integrated ABS Advanced Battery management System that continuously monitors temperature, voltage and load, you therefore benefit from maximum safety, extended runtime and optimum lifespan. The digital display gives a clear, percentage-based charge readout, so you can work efficiently and avoid downtime.

The robust, dust- and corrosion-resistant housing, enhanced with a rubber coating for grip and impact protection, consequently, ensures durability even in tough conditions. The trough handle allows swift, hassle-free removal from any Power X-Change tool.

This Einhell 18 V battery is Twin-Pack compatible, so you can pair two batteries for 36 V applications that demand even more power.

Benefits of the 18 V Einhell 4–6 Ah plus battery

• Two modes for total flexibility –  Choose 4 Ah long‑life mode to extend battery lifespan by up to 300% over standard lithium-ion batteries, or switch to 6 Ah mode for 50% longer runtime than a 4 Ah unit. Ideal for powering demanding cordless tools and pumps through intensive jobs.

• Twin-Pack Technology — With Einhell’s Twin-Pack system, a single battery can power both 18 V and 36 V tools. For high-demand products such as the Flux FBM 4100 battery pump, simply pair two 18 V batteries for 36 V performance.
• PLUS technology: Small, lightweight, powerful — PLUS batteries use advanced 21700 lithium-ion cells. These high efficiency cells deliver strong performance in a compact, lighter package. Fewer cells provide the same power and runtime, but without the extra bulk.

• Smart ABS battery management – Monitors all battery parameters for maximum safety, runtime and pump performance.
• Durable, impact‑resistant housing – Dust and corrosion resistant plastic casing with rubber protection for long‑term durability.

How does Multi‑Ah mode work?

Use the switch to toggle between 4 Ah mode for extended battery life, or 6 Ah mode for maximum runtime, thereby providing added flexibility for different tasks.

Is this battery compatible with the Flux FBM 4100 battery motor?

Yes. This Einhell battery works with the Flux F 400 series battery motor, model FBM 4100. Note, however, that the battery covers must be removed prior to installing the battery packs. To protect the batteries in industrial applications, we recommend purchasing the optional rubber battery covers, available here.

Moreover, these batteries are also compatible with every Power X‑Change tool, including garden equipment, submersible pumps and workshop tools.

Does the battery lose charge when stored?

No. The high‑quality lithium‑ion cells have extremely low self‑discharge, so the battery stays ready to use even after long periods of storage.

• Explore our full range of Einhell batteries and chargers for more options.
• Or contact Flux Pumps UK for expert advice on choosing the right battery for your tools.