Light where it matters
At 45 kg the 412 Ah pack weighs far less than an equivalent lead-acid bank, so it is easier to place, easier to install and kinder to your waterline.
Proteus Eco LiFePO4
Reliable marine power, built by sailors.
Marine-grade 412 Ah LiFePO4 in 12.8 V and 25.6 V — sealed against sea water, protected by a smart BMS and proven aboard yachts across Europe.
412AhNominal
capacity
capacity
45kgPer 12.8 V
unit
unit
6,000cycRated at
90% DoD
90% DoD
IP67Sealed &
waterproof
waterproof
Built in-house
We build the core of the system ourselves.
A lithium bank is the heart of every energy refit we do, so we build our own. Each Proteus Eco battery is a marine-grade 412 Ah LiFePO4 unit, sealed against sea water, protected by a smart BMS, and rated for thousands of cycles rather than hundreds.
The result is a battery you can install with confidence, use to the last amp-hour, and forget about for years — built by people who spend their lives on and around boats.
Current generation
Built, tested and shipped from Cyprus.
Every pack is assembled and quality-checked at our workshop in Limassol before it leaves for the boat — whether that is a single house battery or a full bank for a superyacht.
Why choose Proteus Eco
Key features & advantages
Full capacity, every cycle
A 100% usable depth of discharge means the entire 5.27 kWh is yours to use — no half-empty rule, no compromise on lifespan.
Protected by a smart BMS
A built-in smart BMS and 250 A T-type fuse guard against short circuit, overcharge, deep discharge and temperature extremes — with alarms and Bluetooth built in.
Built for sea water
Sealed to IP67 with a hermetic filler and multi-layered protection — safe even if submerged, and unbothered by the marine environment.
Decades, not seasons
Rated for 6,000 cycles at 90% depth of discharge — around thirty years charged every other day. It outlasts most of what surrounds it aboard.
Read it from your phone
Built-in Bluetooth reports state of charge and pack health straight to your phone, so the whole system stays visible wherever you are.
The difference
How LiFePO4 compares
The same 412 Ah capacity, measured against the alternatives most yachts still carry.
| Proteus Eco LiFePO4 | Lead-acid | Li-ion / Li-cobalt | |
|---|---|---|---|
| Weight (412 Ah) | 45 kg | 115 kg | 56 kg |
| Usable depth of discharge | 100% | 50% | 60% |
| Cycle life | 6,000 cycles at 90% DoD | 300–500 cycles | ~1,000 cycles |
| Battery protection | Built-in smart BMS | None | None |
| Safety | Safe even submerged in water | Toxic materials present | Fire & explosion risk |
Full data
Technical specifications
12.8 V · 412 Ah · 5,273 Wh
25.6 V · 206 Ah
Configurable for 12 V and 24 V systems
Voltage & capacity
- Nominal voltage
- 12.8 V
- Nominal capacity
- 412 Ah
- Nominal energy
- 5,273 Wh
- Energy density
- 164 Wh/kg
- Cycle life
- 6,000 at 90% DoD
- Capacity loss
- <1% / 100 cycles
- Self-discharge
- <3% / month at 25°C
- Internal resistance
- <1.2 mΩ
Discharge
- Max. continuous
- 250 A
- Max. short-term (10s)
- 300 A
- End of discharge voltage
- 11.2 V
Charge
- Charge voltage
- 14 V
- Float voltage
- 13.5 V
- Max. continuous
- 250 A
- Max. short-term (10s)
- 300 A
Operating conditions
- Discharge temp.
- −20 to +50°C
- Charge temp.
- +5 to +50°C
- Storage temp.
- −45 to +70°C
- Humidity
- Max. 95%
Safety & BMS
- BMS
- Smart BMS, 250 A
- Interface
- Bluetooth built-in
- Alarm feature
- Yes, in the BMS
- Internal fuse
- T-type, 250 A
- Protection class
- IP67
- Sealing
- Hermetic, waterproof
General & mounting
- Dimensions (l×w×h)
- 480×255×210 mm
- Weight
- 45 kg
- Power connection
- Male M8 / M10
- Mounting
- Straps & brackets
- Placement
- Sides permitted
Where they go
Ideal for a range of marine applications.
01
Sailing yachts
A perfect service battery bank for sailing yachts, working seamlessly with solar panels for quiet, self-sufficient time at anchor.
02
Motor yachts
Installed as a power bank, they keep every system running smoothly for twelve hours and more while moored or at anchor, with the generator kept in reserve.
03
Electric & hybrid
Configured for 24 V systems, the same cells serve as a reliable house and auxiliary bank for boats with electric or hybrid propulsion.
Straight answers
Questions owners ask.
LiFePO4 is one of the most stable lithium chemistries: it will not enter thermal runaway the way lithium-cobalt cells can. On top of that, every Proteus Eco battery is sealed to IP67 with a hermetic filler, carries a smart BMS and a 250 A T-type fuse, and is safe even if submerged. Safety lives in the design, and that is where our attention goes.
It follows the boat. Most sailing and motor yachts run a 12 V house system, where the 12.8 V 412 Ah unit is the natural fit. Larger banks, higher loads and many electric or hybrid installations are better on 24 V, where the 25.6 V 206 Ah configuration keeps cable sizes and losses down. We size the whole system with you before recommending either.
They are rated for 6,000 cycles at 90% depth of discharge. Charged every other day, that works out at around thirty years of normal cruising. Capacity loss stays under 1% per 100 cycles, so the pack holds its usable energy far longer than the equipment around it.
Very little is required. Self-discharge is under 3% per month, so a battery left over winter loses almost nothing. For long storage we recommend leaving it partially charged in a dry space within the rated temperature range; the BMS looks after the rest and reports its health over Bluetooth whenever you check.
The built-in smart BMS guards against overcharge, deep discharge, short circuit, over-current and temperature extremes, and raises an alarm before any of them become a problem. A 250 A T-type fuse backs it up against short circuit, and the whole state of the pack is visible on your phone over Bluetooth.
Yes. The batteries are one part of what we do — we design and build complete energy systems around them, with solar, charging, protection and monitoring, fabricated and installed by our own team. We travel to the boat wherever she lies across the Mediterranean.
Ready to upgrade
Reliable marine power for your boat.
Tell us the boat, where she lies and what you want running at anchor, and we will recommend the right configuration and size the system around it.
Request a quote