# Marine battery Exide EM900 12V 42Ah 700A AGM

![Marine battery Exide EM900 12V 42Ah 700A AGM](https://baterias.com/1762-home_default/battery-exide-em900-12v-42ah-700a.jpg)

> Exide EM900 marine battery 12V 42Ah 700A AGM. MARINA START AGM range. Dimensions 230×173×206 mm. Demanding marine cranking.

**Category:** [Boat Batteries](https://baterias.com/gb/boat-batteries) → [EXIDE](https://baterias.com/gb/exide)

- **Canonical URL**: https://baterias.com/gb/battery-exide-em900-12v-42ah-700a
- **Language**: en-GB
- **Brand**: EXIDE
- **Reference**: BCOM-EXIDE-EM900
- **EAN**: 3661024036030
- **MPN**: EM900
- **Price**: 519,95 €
- **Stock**: Out of stock

## Technical specifications

| Feature | Value |
|---|---|
| Brand | EXIDE |
| Reference | EM900 |
| Model | EXIDE MARINA START AGM |
| Voltage (V) | 12 V |
| Largo | 230 cm |
| Ancho | 173 cm |
| Alto | 206 cm |
| Peso | 15.8 kg |
| Tecnología | AGM |
| EAN | 3661024036030 |
| Terminal layout | 1+9 |
| Terminal type | SAE M 3/8"- 5/16"&stud |
| Hold down | B7 |
| Cold cranking amps (EN) | 700 A |
| Capacity (C20) | 42 Ah (c20) |

## Quick description

**Exide EM900 12V 42Ah 700A** is a starting battery for boats and motorhomes, with a case reinforced against the vibration of mooring and cruising. All its energy is designed to crank the engine reliably, not to run long loads: for that, fit a separate service bank.

### Why this marine starting battery?

- **Marine design** built for boat swell and vibration
- **Starting in demanding conditions** maximum cranking power
- **Sealed and safe** maintenance-free even when the boat rolls

🔌 Voltage
12 V

⚡ Capacity
42 Ah C20

🔋 Cold cranking
700 A EN-1

📏 Dimensions
230×173×206 mm

⚙️ Technology
AGM

⚖️ Weight
15,8 kg

🏷️ Model
EXIDE MARINA START AGM

## Description

## Marine battery Exide EM900 Marina Start AGM 42Ah 700A 12V

12*V* Voltage
42*Ah* Capacity
700*A* Cold cranking
15.80*kg* Weight

The **Exide EM900** with AGM technology is a marine battery with **42 Ah** and **700 A** of cold cranking current (EN) for motor and sailing boats, both for engine starting and onboard services. Measuring 230 × 173 × 206 mm, it is the direct replacement for boats fitted from the factory with a 42 Ah battery of this format.
- AGM: faster recharging and better cycle resistance than a conventional battery.
- Ready for starting outboard and inboard engines.
- Sealed: no spills or gases in the locker.
- Resistant to humidity and salt air.

### What the Exide EM900 is for

The Exide EM900 is designed for motor and sailing boats, both for engine starting and onboard services. If it is your starter battery, run the services from a separate battery; if it is a service battery, avoid routinely discharging it beyond 50%. Check that it matches your current battery in dimensions, terminals and hold-down: this reference has a weight of 15.80 kg, SAE M 3/8"- 5/16"&stud terminals and B7 hold-down.

### The Exide EM900: Marina Start AGM range and AGM technology

The EM900 is part of the Exide **Marina Start AGM** range. Choosing the right reference within the series comes down to capacity, dimensions and terminals: technology and quality are common to the whole family.
In an AGM battery the electrolyte is absorbed in glass-fibre separators: there is no free liquid, it cannot spill and it can be mounted at an angle. That construction lowers internal resistance, speeds up recharging and multiplies cycle life compared with a conventional battery.

### Dimensions, polarity and mounting

The Exide EM900 is made in the 230 × 173 × 206 mm format and weighs 15.80 kg. It uses a B7 hold-down and SAE M 3/8"- 5/16"&stud terminals, the system that anchors and connects it in the vehicle. Checking the three dimensions and the terminal position before buying avoids the most common mistake when replacing a battery.

### Exide: the maker behind the EM900

With more than a century of history, Exide Technologies manufactures automotive, marine, motorcycle and industrial batteries in Europe. Its presence as original equipment on assembly lines vouches for the quality of every reference. We guarantee that every Exide arrives new, charged and with the manufacturer's full warranty.

### Care and maintenance

As a service battery, avoid routine discharges below 50% to extend its cycle life. At the end of the season, charge the battery fully and, if possible, keep it on a charger over the winter lay-up.

### Official warranty

The Exide EM900 comes with the **manufacturer's official warranty** against manufacturing defects. Deep discharge from winter lay-up without charging is not covered.

### When you get it and how to return it

Same-day dispatch from our warehouse for in-stock orders placed **before [[ks:cutoff]]**: 24-48 working hours in mainland Spain and Portugal, 3 to 5 days in the islands and the rest of Europe. Returns are accepted for **[[ks:return_days]] days** if the battery has not been used (free collection on the Iberian mainland). You will receive tracking by email.

## Frequently asked questions

### Is the Exide EM900 an AGM battery and what are the benefits of AGM?

Yes. The EM900 from Exide uses AGM (Absorbent Glass Mat) technology: a sealed lead-acid battery where the electrolyte is absorbed in a glass-fibre mat. It withstands more charge/discharge cycles than a conventional one, handles heat better and is the required technology for boats with advanced Start-Stop and regenerative braking. Expected lifespan: 5-8 years under normal conditions.

### How do I change this battery step by step?

In most boats it fits in 15-30 minutes with a 10 mm wrench; if the battery is under the seat or in the boot the time can double. See the step-by-step guide on this page. Quick summary: 1) switch off the engine and remove the key; 2) locate the original battery (engine bay, boot or under seat); 3) disconnect the negative (−) terminal first, then the positive (+); 4) loosen the hold-down clamp and remove the old battery; 5) fit the new one in the same orientation — match the polarity shown on the product sheet; 6) connect the positive (+) first, then the negative (−). On boats with Start-Stop or BMS, register the battery via OBD so the alternator applies the correct charging profile.

### How long does the Exide EM900 battery last?

Expected lifespan of the Exide EM900 is 5 to 8 years in mild-climate boat use with Start-Stop. In cold regions it drops slightly due to cold-start stress; in very hot regions it also drops because of electrolyte evaporation. To extend its life: avoid deep discharges (headlights on with engine off), have the alternator checked yearly, and keep the battery clean and properly secured.

### What are the dimensions of the Exide EM900 battery?

Dimensions (length × width × height) are 230×173×206 mm — also written as 230x173x206 mm — following the European DIN standard. Always measure the space in your boat before buying: even one extra millimetre can prevent the hold-down clamp from closing. The height shown includes the terminals.

### Is the EM900 valid for my vehicle?

Three options to confirm: 1) enter your number plate in the finder (DGT/DVLA/KBA auto-detect your model and engine); 2) check the "Compatible vehicles" tab on this page, where we list every vehicle verified by our technical team; 3) if you cannot find your model, message us on WhatsApp with brand, model, engine and year — we reply during business hours (Mon–Fri 10:00–13:30 and 16:40–18:00 (Spanish time, CET)). The EM900 typically fits a wide range of European vehicles thanks to its standard DIN case format.

### Which batteries are equivalent to the Exide EM900?

Directly interchangeable batteries (same dimensions, same polarity, same Ah and CCA) are the OEM equivalents from leading brands: Bosch, Tudor, Exide and, depending on the model, Banner or Yuasa. Exact equivalence depends on technology — an EFB cannot be replaced with a conventional battery in Start-Stop boats. See the "Equivalents" section to view recommended options at the same performance level.


## Technical team (editorial authorship)

The FAQs, guides and comparisons on this site are reviewed by the baterias.com technical team — over 25 years of experience validating automotive batteries.

→ https://baterias.com/gb/technical-team

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*baterias.com — Automotive batteries · 2026-10-03*