TITAN 12V 520Ah Lithium Leisure Battery (Dual DIN)

12.8V | 520Ah | 6,656Wh

Real achievable capacity - up to 550Ah

350mm long x 355mm wide x 190mm high

The 520Ah, in short

The biggest battery in the Diamond range - and the simplest way to describe it is honest: two of our 260Ah Type 019 packs, built side by side into a single sheet-metal case. That gives you 6,656Wh of real, usable energy at 12.8V with 300A continuous BMS output, in a case that keeps the 190mm DIN height. If your install has the floor space of two Type 019 batteries side by side, it has the space for this.

• 6,656Wh usable, up to 550Ah in practice
• 300A continuous BMS discharge
• 49.5kg - replaces 312kg of lead-acid for the same usable Wh
• Native Victron CANBUS and RS485, NMEA2000 on request
• Built-in heater mats, safe charging down to -30°C
• Lifetime, transferable warranty

Case height is 190mm - the same as our DIN range, so it clears under-seat and locker lids that a taller industrial pack never could. All connections are on the front face: M8 bolt terminals plus the comms ports, so it can sit hard against a wall on three sides.

Will it fit your vehicle?

The cell chemistry

All TITAN batteries use lithium iron phosphate (LiFePO4) prismatic cells - the most thermally and chemically stable lithium chemistry available. No cobalt, no nickel, no off-gassing, no acid. The trade-off is a slightly lower cell voltage (3.2V per cell, 4 cells = 12.8V) and lower energy density than the NMC cells used in EVs. In return, you get lifespans that make NMC look disposable: 3,000 to 25,000 cycles depending on use, against NMC's 1,000 to 2,500.

LiFePO4 is now widely considered safer than lead-acid. Cells can be installed in any orientation (upright is optimum), contain no liquid electrolyte, and are fully recyclable.

Cycle life you won't outlive

A cycle is one full discharge plus one full recharge. Count scales with how deep you take each discharge:

• 100% DoD - 3,000 cycles (8.2 years at one cycle a day)
• 80% DoD - 6,000 cycles
• 50% DoD - 12,000 cycles (over 30 years daily use)
• 30% DoD - 15,000+ cycles

For reference, the best lead-acid gel battery tops out at 350-400 cycles at 80% DoD. A TITAN at the same depth gives 6,000 - roughly 15x the service life.

Prismatic, not cylindrical

Our cells are long, flat prisms that fill the rectangular case end to end. Cylindrical cells leave gaps between every cell and are much harder to repair (lots of spot welding), so we pay the extra cost for prismatic and pass the capacity gain back to you. The aluminium cell casing also disperses heat evenly, even at the full 300A BMS allowance - well inside spec (thermal runaway territory doesn't start until around 100°C). Heater mats also work better with prismatic cells - every cell sits against the heating element, rather than only the outer ring of a cylindrical pack.

Capacity, without the weight

Twelve times the usable capacity of lead-acid

Matching this 520Ah in lead-acid means twelve Exide ER550 115Ah batteries paralleled up to 1,380Ah. One TITAN 520Ah replaces the lot - a huge saving in space, weight and cabling, with no gassing so it can live anywhere.

We quote capacity in Wh (Watt-hours) because Ah on its own ignores chemistry. TITAN lithium delivers 100% of rated capacity. Gel manages around 90%, AGM 75%, flooded lead-acid 60%. Factor that in and a TITAN 520Ah has more than double the real-world capacity of a lead-acid battery on the same label rating.

49.5kg. Not 312kg.

There isn't a single lead-acid battery that comes close to this capacity. The honest comparison is twelve ER550-class leisure batteries paralleled together to match the usable Wh - that's 312kg of lead-acid sitting in your install. One TITAN does it in 49.5kg. A 262kg saving matters on a motorhome's drive-axle plate, at the ferry scales, and at the pump.

99% electrically efficient

Almost every watt you put in comes back out. A great partner for solar - no wasted incoming charge - and happy to accept very high charge currents: 0 to 95% in under three hours at 150A+.

The TITAN BMS

The battery management system is the circuit board between the cells and the terminals. It's the difference between a lithium battery that lasts 15 years and one that self-destructs in two. Most brands fit an off-the-shelf board with generic parameters. We don't.

Matched, not off-the-shelf

Our BMS is custom, with parameters tuned to the exact cell spec we use. That lets us run the cells right up to their real safe working limits without compromising protection. It's also how we pull an extra 5-10% usable capacity out of every cell (a 520Ah can show as 550Ah fully charged). We can't guarantee the bonus capacity batch to batch, but the BMS re-maps its 100% reading automatically so the app always shows what you actually have.

11 protections, all self-resetting

Over-discharge, over-voltage, under-voltage, over-current, short-circuit, over-temperature, under-temperature, cell balance faults and more. All protections are temporary - they either self-reset or clear the moment the battery is put back on charge. The 300A continuous current allowance on this model is class-leading thanks to premium MOSFETs, oversized heat sinks and properly sized internal cabling.

Dual active and passive cell balancing

Passive balancing is cheap: cells bleed off to each other and that's it. Active balancing actively moves energy between cells, protecting the weakest cell from doing all the work. Most brands pick one. We run both - passive for small voltage deltas, active for larger ones. Keeps the BMS's own power draw low while still giving you the full benefit of active balancing. It's automatic, most active when charging above 3.4V per cell, and takes full effect between 90-100% SOC.

Self-heating, safely charging down to -30°C

Lithium cannot be charged below 0°C without cell damage. Our built-in heater mats wrap the internal packs and kick in automatically at around 2°C whenever there's an incoming charge current. They draw from the charger first, and if the charger can't keep up, pull up to 3.6A from the battery itself to get cell temperature to 10°C before routing charge back to the cells. Expect roughly 20 extra minutes on your charge time in the cold. Discharge is unaffected and works down to -20°C.

Automatic and user hibernation

A fully discharged lithium battery left for months can be a lithium battery that doesn't come back. Two hibernation modes keep that from happening:

• Automatic: triggers after several days of inactivity at low SOC. The battery stops outputting, but retains enough headroom to last around 6 months (longer on larger packs) before any cell risk. Wakes up the moment you put it on charge or open the app.
• User: triggered by the supplied on/off cable. BMS stays awake, but charge and discharge are disabled. Perfect for winter storage - stops parasitic loads from draining the battery over a season off the road.

Handles high inrush currents

Inverters, water pumps, motor movers and compressors can pull 1,000A+ for a microsecond on start-up. Many BMSs read that as a short circuit and trip. Ours is tuned to ride those spikes without nuisance shutdowns, so start-up loads behave the way they did on your old lead-acid.

Inverter and device communication

Comms ports on the front face let the battery talk to compatible inverters, chargers and GX devices. Defaults to Victron CANBUS (VE.CAN and BMS.CAN) and is compatible with Victron DVCC out of the box. The data mode can be switched to other brands or protocols on request - flag it in the order notes and our engineers will set it before dispatch.

Known working with:

• Victron GX devices (default) - CAN
• Growatt - CAN
• Sacolar - CAN
• Goodwe - CAN
• Voltronic Power - RS485
• Sofar - CAN
• Sorotec - CAN or RS485
• Deye / SunSynk - CAN or RS485
• Solis - CAN
• Luxpower - CAN
• Pylon Tech - CAN or RS485
• Sol-Ark - CAN
• SRNE - RS485
• MUST - CAN
• SMA - CAN
• MEGAREVO - CAN
• MPP Sola - RS485
• TBB Power - CAN
• Senergy - CAN
• Schneider Electric - CAN
• Aiswei - CAN
• Foxess - CAN
• SunGrow - CAN

Cable kits for every protocol are stocked on our store.

Fitment and installation

Two 019 footprints, one battery

The case is exactly what it sounds like: the footprint of two DIN Type 019 batteries side by side, in a single electrocoated sheet-metal case at standard 190mm DIN height. If you're consolidating an existing two- or three-battery bank, measure the tray against 350mm x 355mm and you're done. There are no communication range issues with this metal case - Bluetooth and comms work exactly as they do across the rest of the range.

Double-check your charger. TITAN batteries accept AGM or "Sealed" modes if your charger does not have a dedicated lithium preset. Aim for a maximum charge voltage of 14.4V.

Compatible with split-charge relays and DC-DC chargers out of the box. These are deep-cycle leisure batteries for running equipment - not engine-starting batteries.

Terminals

High-performance copper M8 bolt terminals on the front face - positioned with the comms ports so all cabling approaches from one side. Two M8 bolts and spring washers are included with the battery for direct ring-terminal cabling.

Mounting

190mm tall - the same height as our DIN range, so it fits under seats, in low lockers and beneath bench tops where taller industrial packs won't go. Upright on its base is optimal for longevity and performance, but the cells are stable in any orientation if the install calls for it.

Bluetooth monitoring and the TITAN app

Bluetooth is built in. The free TITAN app (iOS and Android, 10 languages) shows live voltage, current in both amps and watts, SOC as a percentage and in Ah, individual cell voltages, internal temperature, estimated time to full or empty, protection trip history and live balancing activity.

It handles multiple batteries in series or parallel and re-calculates totals automatically, so whether you've got one 520Ah or two in parallel, the figures on screen match the actual pack.

Warranty, longevity and repair

Actual lifetime warranty

We're confident enough in the build to back every grade-A cell battery with a warranty that lasts the lifetime of the battery - fully transferable. Our parent company has been trading continuously since 1948, so we intend to be around to honour it in 20 years' time.

What the warranty doesn't cover is wear. All batteries lose capacity with use - the harder you work them, the faster that happens. LiFePO4 is remarkably resistant: expect a 5-10% capacity drop every decade of normal use. A brand-new 520Ah shows around 550Ah fully charged, a 10-year-old 520Ah around 490Ah, a 20-year-old 520Ah around 445Ah. Natural degradation isn't a valid warranty claim - if a battery stops holding enough capacity for your use, it's time to replace.

The warranty covers components against premature failure caused by manufacturing faults. Full terms are on our warranty page.

Cost over a decade

The TITAN 520Ah sits at £1,499 new. Over its 10-year design life that's £150 a year. The closest lead-acid equivalent - twelve ER550-class leisure batteries in parallel - is around £1,400 a set with a 4-year design life, which means replacing the bank roughly 2.5 times over the same period. Call it £350 a year, with cascading labour each replacement. Around £2,000 saved over 10 years, before you factor in the weight, volume and efficiency benefits. In practice most of our customers see 15-20 years out of a TITAN.

Module-based repair

If something fails we repair the failed module - BMS, balance board, a single cell - rather than replace the whole battery. Lower cost to you, lower carbon footprint, faster turnaround. As a family of battery specialists since the 1950s, there isn't much we haven't already rebuilt.