# Fulbat FL-HU03 · Lawn mower battery 18V 4Ah

![Fulbat FL-HU03 · Lawn mower battery 18V 4Ah](https://bateriasonline.es/396-home_default/fulbat-fl-hu03.jpg)

> Fulbat FL-HU03: 4 Ah lawn mower battery, 146.2×67.6×38.8 mm, lithium. Equivalent to Fulbat FL-HU04. Price on request: ask for a free quote.

**Category:** [Lawn mower and garden machinery batteries](https://bateriasonline.es/en/lawn-mower-garden-batteries) → [Fulbat](https://bateriasonline.es/en/fulbat-batteries)

- **Canonical URL**: https://bateriasonline.es/en/fulbat-fl-hu03
- **Language**: en
- **Brand**: Fulbat
- **Reference**: BOL-FULBAT-FL-HU03
- **MPN**: FL-HU03
- **Last updated**: 2026-10-27

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Fulbat |
| Range | FULBAT Robot Mower |
| Application | Lawn mowers and garden machinery |
| Technology | Lithium |
| Voltage | 18 V |
| Capacity | 4 Ah |
| Length | 146.2 mm |
| Width | 67.6 mm |
| Height | 38.8 mm |
| Weight | 0.49 kg |
| Energy | 72 Wh |

## Quick description

The Fulbat FL-HU03 is a lawn mower battery with 18 V and 4 Ah, measuring 146.2 × 67.6 × 38.8 mm.

## Description

## Where the Fulbat FL-HU03 fits

The Fulbat FL-HU03 is a starter battery for ride-on mowers and garden machinery: small, 12 V and with enough cranking power for single-cylinder engines. Check polarity and terminal type: garden machinery uses several formats.
The FL-HU03 belongs to the Fulbat FULBAT Robot Mower range. [More Fulbat batteries](https://bateriasonline.es/en/fulbat-batteries)

## What it means that the FL-HU03 is lithium

The FL-HU03 is a lithium iron phosphate (LiFePO4) battery with a battery management system (BMS). It needs a charger or regulator with a lithium profile.

## Fulbat FL-HU03 vs FL-HU04: differences

Torn between the FL-HU03 and another similar Fulbat? This is what changes:

| Model | Capacity | Dimensions (mm) | Weight |
|---|---|---|---|
| Fulbat FL-HU03 (this one) | 4 Ah | 146.2 × 67.6 × 38.8 | 0.49 kg |
| Fulbat FL-HU04 | 5.2 Ah | 146.2 × 67.6 × 38.8 | 0.49 kg |

- Fulbat FL-HU04: 1.20 Ah more, the same dimensions.

## Equivalents and alternatives to the Fulbat FL-HU03

Lithium alternatives to the FL-HU03 with its size and polarity.

| Model | Technology | Capacity | Dimensions (mm) |
|---|---|---|---|
| Fulbat FL-HU04 | Lithium | 5.2 Ah | 146.2 × 67.6 × 38.8 |

## Part numbers and codes for the Fulbat FL-HU03

The FL-HU03 is listed under these codes on labels, in garages and in catalogues:

| Commercial reference | FL-HU03 |
|---|---|
| Not to be confused with | Fulbat FL-HU01 (2 Ah), Fulbat FL-HU02 (2.5 Ah), Fulbat FL-HU04 (5.2 Ah) |

## Before ordering the FL-HU03, check this

- Your current battery should say about 4 Ah; a little more is also fine.
- The FL-HU03 needs 146.2 × 67.6 × 38.8 mm of space: measure it with the hold-down clamp in place.

## Frequently asked questions about the Fulbat FL-HU03

### FL-HU03 or FL-HU04: which one suits me?

Compared with the FL-HU03, the Fulbat FL-HU04 has 1.20 Ah more. With 5.2 Ah, the FL-HU04 runs longer between charges than the FL-HU03 (4 Ah). Both measure 146.2 × 67.6 × 38.8 mm, so they fit the same tray.

### How much does the Fulbat FL-HU03 weigh?

0.49 kg, with 4 Ah of capacity. For reference, the Fulbat FL-HU04 (5.2 Ah) weighs 0.49 kg.

### Which battery is equivalent to the Fulbat FL-HU03?

For the FL-HU03, other lithium batteries with its size and polarity: Fulbat FL-HU04.

### Can I use a motorcycle battery in the mower?

If voltage, dimensions, polarity and terminal type match, yes. Many garden batteries are the same format as motorcycle ones.

## More batteries to compare with the FL-HU03

- [More lawn mower and garden machinery batteries](https://bateriasonline.es/en/lawn-mower-garden-batteries)
- [More Fulbat models](https://bateriasonline.es/en/fulbat-batteries)
- [Fulbat FL-HU04](https://bateriasonline.es/en/fulbat-fl-hu04) · 5.2 Ah, 146.2×67.6×38.8 mm

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*bateriasonline.es — Batteries and accessories · 2026-11-10*