Carthago · Premium German motorhomes

The lithium battery for your Carthago motorhome.

Carthago builds some of the most space-efficient and precisely engineered motorhomes on the road, from the compact C2-tourer to the flagship Liner-for-Two. Every model leaves Aulendorf fitted with a sealed AGM - adequate for hook-up touring, limiting off-grid. A TITAN drops into the double-floor battery compartment, gives you the full rated capacity, and handles the deep cycling that serious motorhome travel demands.

Three base vehicles, one approach to the upgrade

Carthago is an independent German manufacturer based in Aulendorf in Baden-Württemberg, building exclusively in the premium tier since 1979 - no entry-level coachbuilts, no overcab family layouts. Every model is constructed around a signature double-floor system: a full-length raised floor that creates a dry, structured storage volume beneath the habitation floor, including a dedicated battery compartment. The range runs across three base vehicles chosen for specific roles. The Fiat Ducato on an AL-KO low-frame Carthago special carries the C1-tourer, C2-tourer, chic c-line and chic e-line as a lighter-weight option. The Mercedes-Benz Sprinter on AL-KO chassis runs alongside the Ducato across those same ranges, offering a wider body, higher ride height and more payload headroom. The Iveco Daily - rear-wheel drive, twin rear tyres, ladder high-frame - carries the heavyweight chic s-plus and Liner-for-Two liner-class models where gross weights and payload demands exceed what the lighter platforms can support.

Some Carthago models are specified from the factory with a larger AGM bank or, on higher-trim variants, a factory lithium option. If your van left the factory with a lithium bank, check the build spec and battery management system before adding or replacing cells - a DC-DC charger is still the right approach when upgrading or supplementing from any Euro 6 base vehicle. If it left with an AGM, the upgrade path is straightforward: a TITAN of the same or similar footprint gives you close to 100% usable capacity from the same compartment space, compared with the 50% you can reliably draw from a sealed lead-acid bank before it starts to degrade.

If you want the broader picture of switching to lithium in a coachbuilt, the motorhome battery guide covers the fundamentals. If you are comparing Carthago against other brands, the motorhome brands hub has the full picture.

Sizing a Carthago by model

A starting point by model range. Carthago's double-floor construction gives most models genuine headroom for a larger bank than the factory fit, and the s-plus and Liner-for-Two can support parallel packs where load demands call for it.

Model rangeTypical useGood fit
C1-tourer T / C2-tourer I (and Malibu sub-brand)Semi-integrated and compact A-class, Fiat or Sprinter, 3.5 t to 4.2 t Weekend and short-trip touring, fridge, lights, heating, phones 150Ah to 180Ah
Chic c-line (A-class, Fiat or Sprinter)Volume A-class, 2-6 berth, full habitation kit Extended touring, off-grid nights, water pump, larger fridge, induction hob 180Ah to 230Ah
Chic e-line (premium A-class, Fiat or Sprinter)Premium A-class, 2-4 berth, high-spec onboard systems Multi-week touring, inverter use, heated habitation, larger appliance loads 230Ah to 330Ah
Chic s-plus / Liner-for-Two (Iveco Daily)Flagship liners, rear-wheel drive, 4.5-7.5 t, separate bedroom and lounge Long-stay off-grid, full induction cooking, air conditioning, inverter, entertainment 230Ah to 330Ah or parallel banks

These are starting points, not fixed rules. The honest figure comes from your own loads, not the model name, so total them in the battery size calculator. Carthago battery compartments and tray dimensions vary by model year and specification level - measure your existing space including terminal clearance before ordering. For the largest liner-class banks, matched packs in parallel where space allows is the right approach.

Where the leisure battery lives in a Carthago

Carthago's signature double-floor construction sets it apart from most coachbuilts. A full-length raised habitation floor creates a structured, weatherproofed storage volume running beneath the van, divided into lined bays for water tanks, gas, cables and battery. The leisure battery typically sits in one of these dedicated compartments, accessed from outside through a lockable service panel on the offside or nearside flanks, or from inside via a lift-out floor section depending on the model and year. Specific positions vary - the handbook is the definitive source for your vehicle, and Carthago's dealer network can confirm compartment dimensions for your model if you are ordering a battery before the van arrives.

Common battery positions across the range are:

  • Dedicated double-floor battery bay. Most chic c-line and chic e-line models house the main leisure battery in a purpose-built bay within the double floor, typically accessible from the offside external service panel. This compartment is designed for a DIN-format battery and usually has enough headroom for a deeper lithium cell.
  • Forward service locker or front habitation bay. Some C1-tourer and C2-tourer layouts site the battery in the front section of the double floor near the cab, alongside the mains charger and fuse board. This keeps cabling runs short to the vehicle battery and the roof solar controller.
  • Multiple-bay bank on s-plus and Liner-for-Two. The Iveco-based liner models often have more than one battery bay, allowing a larger bank split across two compartments or a parallel pair in a single oversized locker. Measure each bay individually - gross weight and compartment depth can differ even where the floor plan looks symmetrical.

The TITAN case is sealed to IP67, which suits the damp and vibration environment of a double-floor bay without modification. The RJ45 comms ports drop to IP32 while a cable is plugged in, so keep any connected port clear of standing water. Always measure your compartment including terminal clearance above the battery - Carthago's double-floor profile is generally generous, but it is not uniform across the range.

Charging a Carthago from alternator, solar and mains

A Carthago charges its leisure battery from three sources: the engine alternator while driving, roof solar through an MPPT controller, and the mains hook-up charger. Lithium accepts charge far faster than the AGM it replaces, so a decent motorway run or a clear afternoon on solar puts real capacity back into the bank rather than a slow overnight trickle.

The alternator is where all three of Carthago's base vehicles need careful thought. Fiat Ducato Euro 6 engines, Mercedes-Benz Sprinter models from around 2014 onwards - and especially the VS30 platform introduced in 2019 with its particularly aggressive variable-voltage management - and the Iveco Daily on the liner-class models all run smart alternators. These variable-voltage systems regulate output based on vehicle demand rather than holding a fixed charging voltage, which means they will not reliably fill a lithium leisure battery on their own. The solution is a DC-DC charger, also called a battery-to-battery charger, wired between the starter battery and the leisure bank. We would fit a Victron Orion every time - it reads the alternator output, steps it up or down to the correct lithium charge voltage, and protects the starter battery from being drawn down. A split-charge relay is less reliable for lithium charging, particularly on the smart-alternator Fiat and Sprinter bases where the variable voltage confuses relay logic and can result in the leisure battery never reaching a full state of charge. Feeding the leisure battery directly from a smart alternator with no DC-DC and no relay is not something we would recommend on any of Carthago's current base vehicles.

Plan the roof system with the solar sizing guide, check your existing mains charger against the compatibility list, and size the battery around the gap your charging sources cannot cover in the hours you are not driving and not on hook-up. Every TITAN carries a custom BMS with a built-in low-temperature heater so it charges safely down to -30C, and each battery comes with a lifetime, fully transferable warranty.

Common questions

What base vehicle does my Carthago use?
Carthago builds across three base vehicles, and the split follows the model range. The C1-tourer T (semi-integrated) and C2-tourer I (narrow A-class) are both available on either a Fiat Ducato on an AL-KO low-frame or a Mercedes-Benz Sprinter on AL-KO - the buyer chooses at order. The chic c-line and chic e-line A-class ranges are similarly offered on both Ducato and Sprinter platforms. The chic s-plus and Liner-for-Two flagship liners are built exclusively on the Iveco Daily with rear-wheel drive and twin rear tyres, which supports the gross weights - sometimes 5 tonnes or more - these models carry. Check your V5C registration document or the Carthago handbook: the base vehicle is listed in the technical data section. That tells you which alternator charging approach applies and which cross-links are relevant to your van.
Do Carthago motorhomes need a DC-DC charger to charge a lithium battery from the engine?
Yes, on all current Carthago base vehicles. The Fiat Ducato Euro 6, the Mercedes-Benz Sprinter (from around 2014, and especially the VS30 from 2019 onwards), and the Iveco Daily used on the s-plus and Liner-for-Two all run variable-voltage smart alternators. These systems regulate charging voltage based on vehicle demand rather than holding a steady output, which means they will not reliably fill a lithium leisure battery directly. A DC-DC charger - we recommend the Victron Orion range - wired between the starter battery and the leisure bank gives the TITAN a clean, controlled charge from the engine without the variable-voltage limitation. A split-charge relay is less reliable in this role on smart-alternator bases; it can cause the leisure battery to plateau below full charge. Check the charger compatibility list for which units work with the TITAN out of the box.
What size lithium battery do I need for a Carthago motorhome?
It depends on the model and how you use it. A compact C1-tourer or C2-tourer typically fits 150Ah to 180Ah well - enough for several off-grid nights with heating, fridge and lighting. A chic c-line A-class with more onboard load suits 180Ah to 230Ah. A chic e-line or the Iveco-based liners running induction cooking, an inverter or air conditioning benefit from 230Ah to 330Ah, or matched packs in parallel where the battery bays allow. Carthago's double-floor compartments are generally generous, but they vary by model year and specification - total your real loads in the battery size calculator and measure the compartment before ordering.
Where is the leisure battery compartment in a Carthago?
Carthago's double-floor construction houses the leisure battery in a dedicated, lined bay within the raised floor structure. On most chic c-line and chic e-line models this is accessed from an external lockable service panel on the vehicle flank. On C1-tourer and C2-tourer layouts it is often positioned toward the front of the double floor near the cab, keeping cabling runs short. On s-plus and Liner-for-Two Iveco-based models there may be more than one battery bay, giving room for a larger or parallel bank. The exact location, tray dimensions and clearance height vary by model year and specification - the Carthago owner's handbook gives the definitive measurements for your vehicle, and Carthago's dealer network can confirm compartment dimensions if needed. Always measure including terminal height before ordering.
Can I upgrade from the factory-fitted AGM or factory lithium option to a TITAN?
For an AGM upgrade, yes - in most cases a TITAN of equivalent or similar footprint fits the same double-floor bay, gives you close to 100% usable capacity compared with the 50% you can reliably draw from a sealed AGM, and handles the deep cycling that motorhome life demands. For a factory lithium upgrade, check the installed battery management system first - if the factory option uses a proprietary BMS with integrated charger logic, replacing or supplementing it requires care to avoid conflicts. The TITAN uses a custom BMS that communicates over RJ45, and is compatible with standard lithium charger profiles from most mains chargers and MPPT solar controllers. Check your mains charger and solar controller against the compatibility list, and fit a DC-DC charger for alternator charging on any Euro 6 Carthago base.
Does TITAN work in cold winter conditions in a Carthago?
Yes. Every TITAN carries a custom BMS with a built-in low-temperature heater that brings the cell temperature up before allowing charge current, so the battery charges safely down to -30C without the risk of lithium plating that would damage a pack without this protection. Discharge is unrestricted down to those temperatures as well, so heating, hot water and habitation loads continue to draw normally in cold conditions. The case is sealed to IP67, which handles the condensation and moisture that can accumulate in a double-floor bay in winter. The RJ45 comms ports drop to IP32 while a monitoring cable is connected, so if you run the TITAN app over the winter keep any plugged port clear of water ingress. Every TITAN comes with a lifetime, fully transferable warranty regardless of how it is used.