# Marine battery Odyssey ODP-AGM27M 85Ah 850A AGM

![Marine battery Odyssey ODP-AGM27M 85Ah 850A AGM](https://baterias.com/1385-home_default/battery-odyssey-odp-agm27m-85ah-850a.jpg)

> Odyssey ODP-AGM27M marine battery 85Ah 850A AGM. ODP range. Dimensions 318×173×224 mm, + terminal on the left. Cranking and house duties.

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

- **Canonical URL**: https://baterias.com/gb/battery-odyssey-odp-agm27m-85ah-850a
- **Language**: en-GB
- **Brand**: ODYSSEY
- **Reference**: BCOM-ODYSSEY-ODP-AGM27M
- **MPN**: ODP-AGM27M
- **Stock**: Out of stock

## Technical specifications

| Feature | Value |
|---|---|
| Brand | ODYSSEY |
| Reference | ODP-AGM27 M |
| Model | ODP |
| Largo | 318 cm |
| Ancho | 173 cm |
| Alto | 224 cm |
| Peso | 27.1 kg |
| Tecnología | AGM |
| Terminal layout | Positive terminal on the left |
| Terminal type | M |
| Cold cranking amps (EN) | 850 |
| Capacity (C20) | 85 Ah (c20) |
| Capacity (C10) | 79 Ah (c10) |

## Quick description

**Odyssey ODP-AGM27M 85Ah 850A** is a marine battery with reinforced anti-vibration case for moorings and offshore use. Tolerates the typical daily cycles on a boat (engine start + night-time services such as lights, sonar, fridge) and holds voltage even when the hull is rolling in open sea.

## Why this marine battery?

- **Marine design** built for boat swell and vibration
- **Dual function** starts the engine and powers onboard services
- **Sealed and safe** maintenance-free even when the boat rolls

⚡ Capacity
85 Ah C20

🔋 Cold cranking
850 A SAE

📏 Dimensions
318×173×224 mm

⚙️ Technology
AGM

🧭 Polarity
Positive on the left

⚖️ Weight
27,1 kg

🏷️ Model
ODP

## Description

## Marine battery Odyssey ODP-AGM27M ODP 85Ah 850A

85*Ah* Capacity
850*A* Cold cranking
27.10*kg* Weight

With **85 Ah** at ** V** and **850 A** of cold cranking current (EN), the **Odyssey ODP-AGM27M** from the **ODP** range is built for motor and sailing boats, both for engine starting and onboard services. It replaces the original battery without adaptation in boats with a 318 × 173 × 224 mm format: same 85 Ah capacity and the positive terminal on the left.
- AGM technology: absorbed electrolyte, no spills, can be mounted at an angle.
- Reinforced case against vibration and swell.
- Powers onboard services: lights, sounder, GPS, fridge.
- Tolerates the daily cycling of a boat in season.

### What the Odyssey ODP-AGM27M is for

On board, the Odyssey ODP-AGM27M provides 85 Ah with a case reinforced against vibration and swell. Keep the terminals clean and protected from salt humidity. Check that it matches your current battery in dimensions, terminals and hold-down: this reference has a weight of 27.10 kg and M terminals.

### Dimensions, polarity and mounting

It has external dimensions of 318 × 173 × 224 mm and weighs 27.10 kg. The positive terminal on the left decides which side the cables end up on: it is the detail that causes most buying mistakes, so check it before ordering. It uses M 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.

### The Odyssey ODP-AGM27M: ODP range and AGM technology

The **ODP** is the Odyssey range the ODP-AGM27M belongs to: it shares the same construction and quality criteria with the rest of the series, and varies in capacity and format to suit each vehicle.
AGM means the acid is held in a glass mat instead of floating free. That is why the battery can be installed in the cabin without gases, survives more cycles and recovers its charge quickly.

### Odyssey: the maker behind the ODP-AGM27M

Odyssey, part of the EnerSys group, makes thin-plate pure-lead (TPPL) batteries: extreme cranking, total vibration resistance and very long service life in motorsport, 4x4, marine and demanding vehicles. All the Odyssey batteries in our catalogue are genuine product, recently manufactured and covered by the manufacturer's warranty.

### Official warranty

The Odyssey ODP-AGM27M comes with the **manufacturer's official warranty** against manufacturing defects. Deep discharge from winter lay-up without charging is not covered.

### Care and maintenance

Charge with a charger that has an AGM mode: it limits the voltage and protects the glass-fibre separators. As a service battery, avoid routine discharges below 50% to extend its cycle life.

### Shipping, delivery and returns

Orders placed **before [[ks:cutoff]]** with the battery in stock ship the same day. Delivery in mainland Spain and Portugal takes 24-48 working hours; for the Balearic and Canary Islands and the rest of the European Union allow 3 to 5 working days. You have **[[ks:return_days]] days** to return an unused battery; in mainland Spain and Portugal collection is free. We email you the tracking number as soon as the parcel ships.

## Frequently asked questions

### How do I fit the ODP-AGM27M model in my boat?

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 Odyssey ODP-AGM27M battery last?

Expected lifespan of the Odyssey ODP-AGM27M is 4 to 7 years in regular use (depends on technology and climate). 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 Odyssey ODP-AGM27M battery?

Dimensions (length × width × height) are 318×173×224 mm — also written as 318x173x224 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.

### Does this battery fit my boat?

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 ODP-AGM27M typically fits a wide range of European vehicles thanks to its standard DIN case format.

### Which batteries are equivalent to the Odyssey ODP-AGM27M?

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 · 2026-10-07*