Greenworks G40B4 40V 4Ah Lithium-Ion Battery

Lithium-Ion: Greenworks G40B4 is a rechargeable 40V battery with a listed 4Ah capacity for compatible Greenworks 40V garden and power tools. Its charge-status LED and claimed compatibility across the range suit owners building around that battery platform, but the listing does not include a charger in its product description.

At a glance

The listing claims compatibility with Greenworks 40V garden and workshop tools. Confirm compatibility with the exact tool model before purchase.
An integrated LED display is described as showing the battery's charge status.
The manufacturer describes deep-discharge protection and says the battery can be recharged without memory effect.
The manufacturer states a 2 year warranty.

Price

£119.99Save 20%

Reference price: ~~£149.99~~

Price checked: 14 Nov 2026

View offer Ahead of Black FridayExplore the selection

Often bought together

Greenworks G40GC Self-Propelled Cordless Electric Garden Cart, 100kg Weight Capacity, 106L, Easy Tipping Function, WITHOUT 40V Battery & Charger, 3 Year Guarantee

£429.99

Pros and cons

Pros

A 4Ah pack offers a higher stated capacity than the 2Ah options also mentioned in the listing, which may suit tools where longer runtime is a priority.
The LED charge display gives a quick indication of remaining charge, according to the product description.
The claimed shared 40V platform may let owners use the battery across compatible Greenworks tools.

Technical specifications

8 specifications

Identity
Brand	Greenworks
Model	G40B4

Power and battery
Battery type	Lithium Ion
Voltage	40 Volts
Capacity	4
Rechargeable	Rechargeable

Dimensions and installation
Dimensions listed	10.2 x 9.5 x 18 centimetres
Weight listed	1.25 Kilograms

What to know before buying

Listing details to confirm

Listing details are inconsistent: the headline says 3-stage LED control while manufacturer copy says 4-stage, and capacity is shown as 4 without a unit in the technical details although the product is described as 4Ah. The description says the battery is supplied without a charger, while the explicit contents list names only the battery and the robust-case wording does not confirm a separate case. Confirm the exact revision and package contents before ordering.

What’s in the box

40V 4Ah batteryIncluded
Robust caseCheck selected pack

Check which accessories are included in your selected pack before buying.

Who is it for?

A good fit for

Greenworks 40V tool owners seeking an additional battery for compatible garden or workshop equipment.
Buyers who value an on-battery charge indicator and a stated 4Ah capacity.

Less suited to

Buyers whose tools use a different voltage platform or whose exact Greenworks model compatibility has not been confirmed.
Anyone needing a complete battery-and-charger kit, unless the selected listing explicitly includes a compatible charger.

Greenworks G40B4 40V 4Ah Lithium-Ion Battery · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.3 / 5 · 295 ratings

5 stars73%73%
4 stars11%11%
3 stars4%4%
2 stars3%3%
1 star9%9%

The supplied evidence includes aggregate star ratings but no customer-comment summary. Those ratings lean positive overall while including a noticeable lower-rated share, so they offer only a broad impression and do not establish specific strengths or faults. For buyers, confirm tool compatibility and charger requirements from the listing rather than treating the rating as evidence of either.

Frequently asked questions

Does the Greenworks G40B4 include a charger?

The product description states that the battery is supplied without a charger. The explicit contents list names the battery only, so check the selected listing if a charger is essential.

Which tools is this battery for?

The manufacturer claims compatibility with Greenworks 40V garden and power tools. Check the exact tool model before buying rather than relying on the voltage alone.

How can I check the remaining charge?

The listing describes an integrated LED display that indicates charge status. It gives conflicting stage counts, so the exact display revision is unclear.