# Fulbat FL-HU04 · Lawn mower battery 18V 5.2Ah

![Fulbat FL-HU04 · Lawn mower battery 18V 5.2Ah](https://bateriasonline.es/401-home_default/fulbat-fl-hu04.jpg)

> Fulbat FL-HU04: 5.2 Ah lawn mower battery, 146.2×67.6×38.8 mm, lithium. Equivalent to Fulbat FL-HU03. 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-hu04
- **Language**: en
- **Brand**: Fulbat
- **Reference**: BOL-FULBAT-FL-HU04
- **MPN**: FL-HU04
- **Last updated**: 2026-11-07

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Fulbat |
| Range | FULBAT Robot Mower |
| Application | Lawn mowers and garden machinery |
| Technology | Lithium |
| Voltage | 18 V |
| Capacity | 5.2 Ah |
| Length | 146.2 mm |
| Width | 67.6 mm |
| Height | 38.8 mm |
| Weight | 0.49 kg |
| Energy | 94 Wh |

## Quick description

Fulbat FL-HU04: lawn mower battery with 18 V and 5.2 Ah, measuring 146.2 × 67.6 × 38.8 mm.

## Description

## The Fulbat FL-HU04 at a glance

The Fulbat FL-HU04 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-HU04 belongs to the Fulbat FULBAT Robot Mower range. [The full range of Fulbat batteries](https://bateriasonline.es/en/fulbat-batteries)

## Lithium technology in the FL-HU04

The FL-HU04 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-HU04 vs FL-HU03

The real differences between the FL-HU04 and the closest Fulbat models:

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

- Fulbat FL-HU03: 1.20 Ah less, the same dimensions.

## Equivalents and alternatives to the Fulbat FL-HU04

Other lithium batteries with the dimensions and polarity of the FL-HU04: lithium needs a charger with a LiFePO4 mode, so it is not mixed with lead-acid.

| Model | Technology | Capacity | Dimensions (mm) |
|---|---|---|---|
| Fulbat FL-HU03 | Lithium | 4 Ah | 146.2 × 67.6 × 38.8 |

## Fulbat FL-HU04 codes and part numbers

The FL-HU04 is listed under these codes on labels, in garages and in catalogues:

| Commercial reference | FL-HU04 |
|---|---|
| Not to be confused with | Fulbat FL-HU01 (2 Ah), Fulbat FL-HU02 (2.5 Ah), Fulbat FL-HU03 (4 Ah) |

## What to look at before buying the FL-HU04

- Your current battery should say about 5.2 Ah; a little more is also fine.
- Length, width and height of the FL-HU04: 146.2 × 67.6 × 38.8 mm.

## Frequently asked questions about the Fulbat FL-HU04

### Fulbat FL-HU04 or FL-HU03?

Compared with the FL-HU04, the Fulbat FL-HU03 has 1.20 Ah less. 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-HU04 weigh?

The FL-HU04 weighs 0.49 kg. For reference, the Fulbat FL-HU03 (4 Ah) weighs 0.49 kg.

### Which battery is equivalent to the Fulbat FL-HU04?

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

### Which charger does the Fulbat FL-HU04 need?

A charger or regulator with a lithium/LiFePO4 mode (14.2-14.6 V for 12 V). Do not use lead-acid chargers with a desulphation stage and do not charge it below 0 °C.

## Keep comparing: alternatives to the FL-HU04

- [Other lawn mower and garden machinery batteries](https://bateriasonline.es/en/lawn-mower-garden-batteries)
- [Full Fulbat catalogue](https://bateriasonline.es/en/fulbat-batteries)
- [Fulbat FL-HU07](https://bateriasonline.es/en/fulbat-fl-hu07) · 5.2 Ah, 220.7×67.3×22.4 mm
- [Fulbat FL-AL02](https://bateriasonline.es/en/fulbat-fl-al02) · 5 Ah, 128×69×50 mm
- [Fulbat FL-RM03](https://bateriasonline.es/en/fulbat-fl-rm03) · 6.6 Ah, 216×56×79 mm

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