# Marine battery Fullriver FT825-78 12V 65Ah 825A AGM

![Marine battery Fullriver FT825-78 12V 65Ah 825A AGM](https://baterias.com/3168-home_default/battery-fullriver-ft825-78-12v-65ah-825a.jpg)

> Fullriver FT825-78 marine battery 12V 65Ah 825A AGM. Full Throttle Series range. Dimensions 261×172×211 mm. Cranking and house duties.

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

- **Canonical URL**: https://baterias.com/gb/battery-fullriver-ft825-78-12v-65ah-825a
- **Language**: en-GB
- **Brand**: FULLRIVER
- **Reference**: BCOM-FULLRIVER-FT825-78
- **MPN**: FT825-78
- **Price**: 327,95 €
- **Stock**: Out of stock

## Technical specifications

| Feature | Value |
|---|---|
| Brand | FULLRIVER |
| Reference | FT825-78 |
| Model | Full Throttle Series |
| Voltage (V) | 12 V |
| Largo | 261 cm |
| Ancho | 172 cm |
| Alto | 211 cm |
| Peso | 21.1 kg |
| Tecnología | AGM |
| EAN | 810233030527 |
| Terminal type | M8 + TP29 + FR45 |
| Cold cranking amps (EN) | 825 |
| Capacity (C20) | 65 |
| Case type | 78 |

## Quick description

**Fullriver FT825-78 12V 65Ah 825A** 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

🔌 Voltage
12 V

⚡ Capacity
65 Ah C20

🔋 Cold cranking
825 A EN-1

📏 Dimensions
261×172×211 mm

⚙️ Technology
AGM

⚖️ Weight
21,1 kg

🏷️ Model
Full Throttle Series

## Description

## Marine battery Fullriver FT825-78 Full Throttle Series 65Ah 825A 12V

12*V* Voltage
65*Ah* Capacity
825*A* Cold cranking
21.10*kg* Weight

The **Fullriver FT825-78 marine battery** offers **12 V**, **65 Ah** and **825 A** of cold cranking current (EN) from the **Full Throttle Series** range with AGM technology, designed for motor and sailing boats, both for engine starting and onboard services. Its 261 × 172 × 211 mm make it the exact replacement for the 65 Ah battery fitted as standard to many boats.
- Ready for starting outboard and inboard engines.
- AGM: faster recharging and better cycle resistance than a conventional battery.
- Resistant to humidity and salt air.
- Sealed: no spills or gases in the locker.

### What the Fullriver FT825-78 is for

On board, the Fullriver FT825-78 provides 65 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 21.10 kg and M8 + TP29 + FR45 terminals.

### Dimensions, polarity and mounting

The Fullriver FT825-78 is made in the 261 × 172 × 211 mm format and weighs 21.10 kg. It uses M8 + TP29 + FR45 terminals, the system that anchors and connects it in the vehicle. For a direct replacement, the current battery tray must accept these dimensions and the same terminal layout; otherwise adapters will be needed or the hold-down will change.

### Why choose Fullriver batteries

Fullriver specialises in deep-cycle AGM batteries for mobility, marine, solar and traction. Its DC and HC series are known for their tolerance to deep discharge and long cycle life. We guarantee that every Fullriver arrives new, charged and with the manufacturer's full warranty.

### The Fullriver FT825-78: Full Throttle Series range and AGM technology

The FT825-78 is part of the Fullriver **Full Throttle Series** 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.

### Usage and maintenance tips

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.

### Warranty and coverage

The Fullriver FT825-78 comes with the **manufacturer's official warranty** against manufacturing defects. Deep discharge from winter lay-up without charging is not covered.

### Delivery times and returns

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 this battery AGM? What is it for?

Yes. The FT825-78 from Fullriver 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 fit the FT825-78 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.

### What is the service life of the FT825-78 model?

Expected lifespan of the Fullriver FT825-78 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 size is this battery?

Dimensions (length × width × height) are 261×172×211 mm — also written as 261x172x211 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 FT825-78 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 FT825-78 typically fits a wide range of European vehicles thanks to its standard DIN case format.

### Which batteries are equivalent to the Fullriver FT825-78?

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.


## Equivalent batteries

- [FULLRIVER FT825-34](https://baterias.com/gb/battery-fullriver-ft825-34-12v-65ah-825a)

## Technical team (editorial authorship)

The FAQs, guides and comparisons on this site are reviewed by the baterias.com technical team — automotive battery specialists since 2015.

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

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