# Fulbat AUX14-J · Auxiliary battery 12V 14Ah

![Fulbat AUX14-J · Auxiliary battery 12V 14Ah](https://bateriasonline.es/592-home_default/fulbat-aux14-j.jpg)

> Fulbat AUX14-J: 14 Ah auxiliary battery, 150×87×145 mm, positive terminal on the left, AGM. Equivalent to Exide EK131 and Exide EK151.

**Category:** [Auxiliary batteries (back-up and in-vehicle service)](https://bateriasonline.es/en/auxiliary-backup-batteries) → [Fulbat](https://bateriasonline.es/en/fulbat-batteries)

- **Canonical URL**: https://bateriasonline.es/en/fulbat-aux14-j
- **Language**: en
- **Brand**: Fulbat
- **Reference**: BOL-FULBAT-AUX14-J
- **MPN**: AUX14-J
- **Last updated**: 2026-11-06

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Fulbat |
| Range | FULBAT Auxiliary AGM |
| Application | Auxiliary and back-up use |
| Technology | AGM |
| Voltage | 12 V |
| Capacity | 14 Ah |
| Length | 150 mm |
| Width | 87 mm |
| Height | 145 mm |
| Weight | 4.62 kg |
| Polarity | Positive terminal on the left |

## Quick description

Fulbat AUX14-J: auxiliary battery (AGM) with 12 V and 14 Ah, measuring 150 × 87 × 145 mm, with the positive terminal on the left.

## Description

## Where the Fulbat AUX14-J fits

The Fulbat AUX14-J is the second battery fitted in many modern cars. Without it, Start-Stop or back-up warnings appear on the dashboard.
The AUX14-J belongs to the Fulbat FULBAT Auxiliary AGM range. [The full range of Fulbat batteries](https://bateriasonline.es/en/fulbat-batteries)

## Equivalents and alternatives to the Fulbat AUX14-J

As the AUX14-J 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 | Dimensions (mm) |
|---|---|---|---|
| Varta AUX14 | AGM | 13 Ah | 150 × 87 × 146 |
| Kronobat AUX14 | AGM | 13 Ah | 150 × 87 × 146 |
| Exide EK131 | AGM | 13 Ah | 150 × 90 × 145 |
| Exide EK151 | AGM | 15 Ah | 150 × 90 × 145 |
| Tudor TK151 | AGM | 15 Ah | 150 × 90 × 145 |
| Tudor TK131 | AGM | 13 Ah | 150 × 90 × 145 |

## Fulbat AUX14-J vs AUX14 and AUX12

The real differences between the AUX14-J and the closest Fulbat models:

| Model | Capacity | Dimensions (mm) | Positive | Weight |
|---|---|---|---|---|
| Fulbat AUX14-J (this one) | 14 Ah | 150 × 87 × 145 | left | 4.62 kg |
| Fulbat AUX14 | 12.6 Ah | 150 × 87 × 145 | left | 4.53 kg |
| Fulbat AUX12 | 10.5 Ah | 150 × 87 × 130 | left | 4.1 kg |

- Fulbat AUX14: 1.40 Ah less, the same dimensions.
- Fulbat AUX12: 3.5 Ah less, a different case (150 × 87 × 130 mm).

## Inside the AUX14-J: AGM technology

Inside, the AUX14-J has glass fibre separators (AGM) that hold the electrolyte. It is fitted in cars with advanced Start-Stop and in deep-cycle equipment.

## Before ordering the AUX14-J, check this

- Measure the space: the AUX14-J takes up 150 × 87 × 145 mm.
- The AUX14-J has the positive terminal on the left: compare it with your current battery.
- Capacity of the AUX14-J: 14 Ah; the same as your current battery or slightly more is fine.

## Fulbat AUX14-J codes and part numbers

Shops, garages and catalogues identify the AUX14-J with these codes:

| Commercial reference | AUX14-J |
|---|---|
| Not to be confused with | Fulbat AUX14 (12.6 Ah) |

## Frequently asked questions about the Fulbat AUX14-J

### Fulbat AUX14-J or AUX14?

Compared with the AUX14-J, the Fulbat AUX14 has 1.40 Ah less. With 14 Ah, the AUX14-J runs longer between charges than the AUX14 (12.6 Ah). Both measure 150 × 87 × 145 mm, so they fit the same tray.

### How much does the Fulbat AUX14-J weigh?

The AUX14-J weighs 4.62 kg. For reference, the Fulbat AUX14 (12.6 Ah) weighs 4.53 kg.

### Which battery is equivalent to the Fulbat AUX14-J?

Only other AGM batteries with its dimensions and polarity: Varta AUX14, Kronobat AUX14 and Exide EK131. Neither an EFB nor a conventional battery replaces the AUX14-J.

### Which side is the positive terminal on the Fulbat AUX14-J?

The AUX14-J has the positive terminal on the left, looking at the battery from its long side with the terminals closest to you.

## Keep comparing: alternatives to the AUX14-J

- [More auxiliary batteries (back-up and in-vehicle service)](https://bateriasonline.es/en/auxiliary-backup-batteries)
- [The whole Fulbat range](https://bateriasonline.es/en/fulbat-batteries)
- [Varta AUX14](https://bateriasonline.es/en/varta-aux14) · 13 Ah, 200 A, 150×87×146 mm
- [Kronobat AUX14](https://bateriasonline.es/en/kronobat-aux14) · 13 Ah, 200 A, 150×87×146 mm

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