# Fulbat SLA12-20 · Lawn mower battery 12V 21.1Ah 180A

![Fulbat SLA12-20 · Lawn mower battery 12V 21.1Ah 180A](https://bateriasonline.es/607-home_default/fulbat-sla12-20.jpg)

> Fulbat SLA12-20: 21.1 Ah lawn mower battery, 180 A (EN), 182×77×168 mm, positive terminal on the right, AGM. Equivalent to Fulbat SLA12-22.

**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-sla12-20
- **Language**: en
- **Brand**: Fulbat
- **Reference**: BOL-FULBAT-SLA12-20
- **MPN**: SLA12-20
- **Last updated**: 2026-10-27

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Fulbat |
| Range | FULBAT Lawn & Garden SLA |
| Application | Lawn mowers and garden machinery |
| Technology | AGM |
| Voltage | 12 V |
| Capacity | 21.1 Ah |
| Cold cranking amps (EN) | 180 A |
| Length | 182 mm |
| Width | 77 mm |
| Height | 168 mm |
| Weight | 5.3 kg |
| Polarity | Positive terminal on the right |

## Quick description

The Fulbat SLA12-20 is a lawn mower battery with 12 V, 21.1 Ah and 180 A cold cranking current, measuring 182 × 77 × 168 mm, with the positive terminal on the right.

## Description

## Where the Fulbat SLA12-20 fits

The Fulbat SLA12-20 starts ride-on mowers and garden tractors. Check polarity and terminal type: garden machinery uses several formats.
The SLA12-20 belongs to the Fulbat FULBAT Lawn & Garden SLA range. [See all Fulbat batteries](https://bateriasonline.es/en/fulbat-batteries)

## Inside the SLA12-20: AGM technology

Inside, the SLA12-20 has glass fibre separators (AGM) that hold the electrolyte. The SLA12-20 needs a charger with an AGM mode that does not exceed 14.7 V.

## Fulbat SLA12-20 vs SLA12-22 and SLA12-18: which one to choose?

Torn between the SLA12-20 and another similar Fulbat? This is what changes:

| Model | Capacity | Cold cranking (EN) | Dimensions (mm) | Positive | Weight |
|---|---|---|---|---|---|
| Fulbat SLA12-20 (this one) | 21.1 Ah | 180 A | 182 × 77 × 168 | right | 5.3 kg |
| Fulbat SLA12-22 | 23.1 Ah | 210 A | 182 × 77 × 168 | right | 6.3 kg |
| Fulbat SLA12-18 | 18.9 Ah | 150 A | 182 × 77 × 168 | right | 4.95 kg |

- Fulbat SLA12-22: 2 Ah more, 30 A more cranking power, the same dimensions.
- Fulbat SLA12-18: 2.20 Ah less, 30 A less cranking power, the same dimensions.

## Equivalents and alternatives to the Fulbat SLA12-20

As the SLA12-20 is an AGM battery, we only list other AGM batteries with its dimensions and polarity: neither an EFB nor a conventional battery can replace it.

| Model | Technology | Capacity | Cold cranking (EN) | Dimensions (mm) |
|---|---|---|---|---|
| Fulbat SLA12-22 | AGM | 23.1 Ah | 210 A | 182 × 77 × 168 |

## Fulbat SLA12-20 codes and part numbers

This is how the Fulbat SLA12-20 appears on the label and in parts catalogues:

| Commercial reference | SLA12-20 |
|---|---|
| Not to be confused with | Fulbat SLA12-22 (23.1 Ah, 210 A) |

## Check this before ordering the Fulbat SLA12-20

- The SLA12-20 delivers 180 A cold cranking (EN standard); do not go below what your original battery states.
- Your current battery should say about 21.1 Ah; a little more is also fine.
- The SLA12-20 has the positive terminal on the right: compare it with your current battery.
- Length, width and height of the SLA12-20: 182 × 77 × 168 mm.

## Frequently asked questions about the Fulbat SLA12-20

### Fulbat SLA12-20 or SLA12-22?

Compared with the SLA12-20, the Fulbat SLA12-22 has 2 Ah more and 30 A more cranking power. If your current battery says 210 A or more, choose the SLA12-22; if it says 180 A or less, the SLA12-20 is enough. Both measure 182 × 77 × 168 mm, so they fit the same tray.

### How much does the Fulbat SLA12-20 weigh?

The SLA12-20 weighs 5.3 kg. For reference, the Fulbat SLA12-22 (23.1 Ah) weighs 6.3 kg.

### Which battery is equivalent to the Fulbat SLA12-20?

Only other AGM batteries with its dimensions and polarity: Fulbat SLA12-22. Neither an EFB nor a conventional battery replaces the SLA12-20.

### Which side is the positive terminal on the Fulbat SLA12-20?

The SLA12-20 has the positive terminal on the right, looking at the battery from its long side with the terminals closest to you.

## More batteries to compare with the SLA12-20

- [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 SLA12-22](https://bateriasonline.es/en/fulbat-sla12-22) · 23.1 Ah, 210 A, 182×77×168 mm

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