A campervan or motorhome lithium battery upgrade typically costs between £600 and £2,500, depending on the battery capacity and how much of the existing charging system needs changing.

A straightforward battery replacement can sit towards the lower end of that range. A more complete upgrade involving a larger lithium battery, DC-to-DC charger, mains charger, battery monitor, cabling and protection can cost considerably more.

High-capacity systems designed to run powerful inverters or support long periods off-grid can exceed £3,000–£5,000.

The important point is that a lithium upgrade is not always as simple as removing an AGM battery and fitting a lithium battery in its place.

At WeConvert, we provide campervan and motorhome lithium battery upgrades from our Blackburn workshop. We assess the existing battery, alternator charging, solar controller, mains charger, cables and intended electrical use before recommending a system.

Typical Campervan Lithium Battery Upgrade Costs

The following figures are realistic planning ranges for UK installations. They are not fixed quotations.

Current battery prices illustrate why there can be such a wide range. UK-listed examples include approximately £320–£390 for some 100–105Ah batteries, around £700 for a 230Ah model and roughly £900–£1,200 for certain 340–460Ah batteries before installation or wider system alterations. Simple supplied-and-fitted offers also exist from around £444, but these assume the vehicle is suitable for a straightforward replacement.

Your actual price depends much more on the existing installation than the headline cost of the battery.

What Is a Lithium Leisure Battery?

Most campervan lithium batteries use lithium iron phosphate, usually shortened to:

• LiFePO4
• LFP
• Lithium leisure battery

This chemistry is widely used in campervans, motorhomes, boats and off-grid systems.

A lithium leisure battery normally includes an internal or external battery-management system, known as a BMS.

The BMS monitors and protects the battery against conditions such as:

• Excessive charge voltage
• Excessive discharge
• High current
• Short circuit
• High temperature
• Low-temperature charging
• Cell imbalance

The exact protection features, current limits and operating temperatures vary between manufacturers and battery models.

Do not assume that all batteries advertised as 100Ah lithium products provide the same performance. Their BMS ratings, warranty terms, certifications, construction and support can be very different.

Is a Lithium Upgrade Just a Battery Swap?

Sometimes—but not always.

A genuine drop-in replacement may be possible where the existing installation already has:

• A suitable charging profile
• Appropriate charge-current limits
• Adequate cables
• Correct fusing
• Secure battery mounting
• Suitable low-temperature protection
• A compatible alternator-charging arrangement

However, many older campervans and motorhomes were designed around:

• Flooded lead-acid batteries
• AGM batteries
• Gel batteries

Their existing chargers may not be designed to charge lithium batteries correctly.

Before fitting lithium, the following should be checked:

1. Alternator or engine charging
2. Mains battery charger
3. Solar charge controller
4. Cable sizes
5. Fuses and isolators
6. Battery monitor
7. Physical installation space
8. Battery restraint
9. Cold-weather protection
10. Maximum expected current

This assessment is where a proper upgrade differs from simply buying a battery online and connecting it to the existing terminals.

1. The Cost of the Lithium Battery

The battery is usually the largest individual component cost.

100–150Ah lithium battery

A battery in this range is often suitable for:

• Weekend use
• Compressor fridge
• Lighting
• Water pump
• Diesel heater
• Device charging
• Modest inverter use

Typical battery-only cost:

Approximately £320–£700

A 100–150Ah battery may fit within the space previously occupied by a single lead-acid or AGM battery, although physical dimensions and terminal positions must still be checked.

200–230Ah lithium battery

This range may suit owners who:

• Spend longer off-grid
• Use a fridge continuously
• Run a diesel heater
• Charge laptops
• Use a medium-sized inverter
• Have limited opportunity to connect to mains electricity

Typical battery-only cost:

Approximately £650–£1,200

For example, a current UK-listed 230Ah Roamer battery is priced at about £699 before fitting.

300–460Ah lithium battery

Higher-capacity systems are commonly considered for:

• Long-term touring
• Full-time van use
• Large inverters
• Electric cooking
• Frequent remote working
• High daily consumption
• Extended periods without hook-up

Typical battery-only cost:

Approximately £900–£1,600+

Current UK listings show examples around £899 for 340Ah and approximately £1,199 for 460Ah, although specifications, current limits and warranties vary.

A large battery is not automatically the correct choice. The vehicle still needs enough charging capacity to replenish it.

2. DC-to-DC Charger Costs

The alternator-charging system may need upgrading when lithium is fitted.

Older conversions may use a voltage-sensitive split-charge relay. This arrangement can be unsuitable where:

• The vehicle has a smart alternator
• The lithium battery can accept a high current
• The existing cable is undersized
• Charging voltage is poorly controlled
• Battery separation is unreliable

A DC-to-DC charger regulates the charging current and provides a charging profile for the leisure battery.

Typical installed cost:

Approximately £450–£900

This may include:

• Charger
• High-current cable
• Fuses
• Fuse holders
• Ignition or engine-run signal
• Mounting
• Configuration
• Labour
• Testing

The price depends on:

• Charger output
• Distance between batteries
• Vehicle charging system
• Cable route
• Access
• Existing wiring
• Battery capacity

A larger charger is not always better.

The current must remain within the limits of:

• Vehicle alternator
• Lithium battery BMS
• Charger
• Wiring
• Fuses
• Connections

Some modern DC-to-DC chargers include configurable low-temperature shutdown to prevent charging a lithium battery outside its permitted temperature range.

3. Mains Charger Costs

The existing mains charger must be checked for lithium compatibility.

An older charger may use a profile designed for AGM, gel or flooded lead-acid batteries.

Possible issues include:

• Unsuitable charge voltage
• Equalisation mode
• Excessive absorption time
• Inappropriate float behaviour
• No lithium profile
• Charger too small
• Charger unable to respond to the battery BMS
• No low-temperature charging control

Typical installed replacement cost:

Approximately £300–£800

The final cost depends on whether the charger is:

• A simple standalone unit
• Integrated into a motorhome power-distribution system
• Combined with an inverter
• Located behind furniture
• Connected through manufacturer-specific equipment

Some chargers specifically support LiFePO4 batteries, but compatibility must still be checked against the chosen battery’s charging requirements. For example, Victron’s lithium-capable charger guidance warns against charging LiFePO4 batteries below their permitted temperature.

A factory motorhome may require more investigation than a self-build campervan because the charger, control panel and distribution system can be closely integrated.

4. Solar Charge Controller Costs

An existing solar controller may be:

• Fully compatible
• Compatible after configuration
• Too small
• Unable to disable equalisation
• Missing low-temperature control
• Unsuitable for the new battery

Typical installed solar-controller upgrade:

Approximately £250–£650

The correct controller depends on:

• Solar-panel wattage
• Panel voltage
• Series or parallel arrangement
• Battery voltage
• Expected current
• Battery requirements
• Cable size

Lithium charging settings typically differ from those used for lead-acid batteries. For example, lithium-oriented configurations may disable equalisation and temperature compensation while applying a low-temperature charge cut-off. The precise settings must come from the selected battery manufacturer rather than a generic internet profile.

For solar problems, read Campervan or Motorhome Solar Panel Not Charging the Battery?.

5. Battery Monitor and Shunt Costs

A proper battery monitor is particularly useful with lithium.

Basic voltage displays are less helpful because lithium batteries can maintain a relatively stable voltage through much of their discharge.

A shunt-based monitor measures the current entering and leaving the battery and estimates:

• State of charge
• Current use
• Amp-hours consumed
• Remaining time
• Historical usage

Typical installed cost:

Approximately £250–£500

The installation may include:

• Shunt
• Display or Bluetooth monitor
• New negative cables
• Busbar
• Re-routing existing connections
• Configuration
• Testing

All significant loads and charging sources must be connected on the correct side of the shunt. Otherwise, the monitor will not accurately account for the energy entering or leaving the battery.

A monitor can improve visibility, but it does not increase the battery’s capacity or fix an inadequate charging system.

6. Cabling, Fuses and Isolators

A lithium battery may be capable of supplying or accepting more current than the original battery system.

The existing installation should be assessed for:

• Cable cross-sectional area
• Cable length
• Insulation condition
• Terminations
• Fuse type
• Fuse rating
• Isolator rating
• Busbars
• Earth or negative return
• Heat damage
• Voltage drop

Typical cost for cabling and protection alterations:

Approximately £150–£700

The figure can be higher where the vehicle needs:

• Long high-current cable runs
• Large inverter cables
• New busbars
• Multiple high-current fuses
• Main battery isolator
• Rebuilt distribution
• Removal of poor existing wiring

A fuse should protect the cable, not simply match the highest number printed on the battery or appliance.

Do not increase a fuse rating without checking the complete circuit.

7. Low-Temperature Charging Protection

Lithium batteries should only be charged within the temperature range specified by their manufacturer.

Some batteries include:

• Automatic low-temperature charge cut-off
• Internal heating
• External temperature sensor
• BMS control of connected chargers

Others rely on the external charging equipment to stop charging.

For example, Victron’s Lithium Battery Smart range allows charging only from 5°C to 50°C, while other batteries may specify a 0°C minimum. The battery’s own instructions always take priority.

This is relevant in Blackburn and throughout Lancashire, particularly where a leisure battery is mounted:

• Beneath a vehicle
• In an unheated garage
• Inside an external locker
• Against a cold metal floor
• Away from the heated living area

Possible solutions include:

• Battery with internal low-temperature protection
• Heated battery
• External temperature sensing
• Charger with temperature-controlled shutdown
• Moving the battery to a more suitable location

Cold-weather requirements can add approximately:

£100–£500+

The cost depends on whether protection is already included in the battery or requires wider system changes.

8. Battery Mounting and Physical Alterations

Lithium batteries are often lighter than equivalent lead-acid banks, but they must still be mounted securely.

The installation may need:

• New retaining bracket
• Battery tray
• Protective enclosure
• Seat-base modification
• Ventilation changes
• Relocation
• Terminal covers
• Insulated barriers
• Service access
• Protection from stored items

Typical cost:

Approximately £75–£500+

A battery should not be left loose inside a cupboard or beneath a seat.

It must be protected against:

• Vehicle movement
• Impact
• Metal objects falling across terminals
• Water
• Heat
• Cable strain
• Accidental short circuit

Large batteries may also require the layout to be reconsidered because of their dimensions, terminal positions and higher current capability.

9. Inverter Upgrades

A lithium battery is often fitted because the owner wants to operate mains appliances away from hook-up.

That may require an inverter.

Common intended loads include:

• Laptop chargers
• Television
• Coffee machine
• Microwave
• Hairdryer
• Induction hob
• Air fryer
• Power tools

Typical installed inverter cost:

Large inverter systems may require:

• High-current cables
• Larger fuses
• Busbars
• Remote switch
• Consumer-unit alterations
• Changeover equipment
• Additional socket circuit
• Earthing arrangements
• RCD assessment
• Larger battery
• Greater charging capacity

A lithium battery does not automatically make every household appliance practical inside a campervan.

The complete system must be designed around the appliance’s:

• Continuous power
• Startup surge
• Operating duration
• Daily energy use

Example 1: Basic 100Ah Lithium Upgrade

A small campervan has:

• One ageing 100Ah AGM battery
• Existing lithium-compatible solar controller
• Suitable mains charger
• Modern DC-to-DC charger
• No large inverter

The upgrade may require:

• 100–150Ah lithium battery
• New battery restraint
• Minor cable alterations
• Fuse check
• Charger configuration
• Installation and testing

Indicative installed cost:

£600–£1,000

This is the closest example to a genuine drop-in replacement.

It should not be assumed until the charging equipment has been identified and checked.

Example 2: 100Ah Lithium With Charging Upgrades

A campervan has:

• Old AGM battery
• Split-charge relay
• Basic voltage display
• Older mains charger
• Solar controller with no suitable lithium profile

The work may include:

• 100–150Ah lithium battery
• DC-to-DC charger
• Mains charger or charger configuration
• Solar-controller replacement
• Battery monitor
• Fuses and cable alterations

Indicative installed cost:

£1,200–£2,000

Although the battery is relatively small, the supporting equipment makes this a more substantial upgrade.

Example 3: 230Ah Off-Grid Upgrade

An owner wants more capacity for:

• Compressor fridge
• Diesel heater
• Laptop use
• Television
• Longer off-grid trips
• Occasional inverter use

The system may include:

• 200–230Ah lithium battery
• 30–50A DC-to-DC charger
• Compatible mains charger
• MPPT solar controller
• Battery monitor
• New busbars
• Main fuses and isolator
• Cable upgrades

Indicative installed cost:

£1,800–£3,000

The actual figure depends heavily on whether existing solar panels and chargers can be retained.

Example 4: High-Capacity Lithium and Inverter System

The owner wants to run:

• Microwave
• Coffee machine
• High-power sockets
• Work equipment
• Occasional electric cooking

The installation may include:

• 300–460Ah lithium battery
• 50A or larger alternator charging
• Inverter-charger
• Battery monitor
• High-current busbars
• Large battery cables
• Multiple fuses
• Solar expansion
• Consumer-unit and changeover work

Indicative installed cost:

£3,500–£6,000+

This is no longer simply a battery upgrade. It is a redesign of the vehicle’s off-grid electrical system.

Example 5: Factory Motorhome Lithium Conversion

Factory-built motorhomes may include:

• Integrated charger and distribution unit
• Manufacturer control panel
• Separate starter and habitation monitoring
• Electric step
• Heating controls
• Fridge control
• Vehicle-specific relays
• Existing solar equipment

Changing one part can affect the wider system.

The work may require:

• Compatibility research
• Battery replacement
• Charger replacement
• DC-to-DC charger
• Control-panel configuration
• Additional monitor
• Wiring modifications
• Further testing

Indicative cost:

£1,500–£3,500+

An inspection is usually needed before a meaningful price can be given.

What Determines the Final Installation Price?

Battery capacity

A larger battery generally costs more, but size alone does not determine the total.

A lower-cost battery combined with extensive charger and wiring alterations can cost more to install than a premium battery in a modern, compatible system.

Existing equipment

The installer needs to identify:

• Mains charger
• Alternator charger
• Solar controller
• Inverter
• Battery monitor
• Distribution equipment

Labels and model numbers are often needed before compatibility can be confirmed.

Access

Labour increases where equipment is:

• Beneath fixed furniture
• Under a seat
• Behind a water tank
• Inside a sealed compartment
• Surrounded by undocumented wiring
• Difficult to remove safely

Existing installation quality

A tidy and documented system is easier to upgrade than one containing:

• Unlabelled cables
• Multiple direct battery connections
• Undersized wiring
• Poor crimps
• Household connectors
• Melted fuse holders
• Unsupported equipment
• Previous modifications

Unsafe or unsuitable existing work may need correcting before lithium can be fitted.

Intended appliances

A battery for lights, a fridge and a water pump is a different proposition from a system expected to operate:

• Induction cooking
• Microwave
• Hairdryer
• Coffee machine
• Air fryer
• Large power tools

High-power appliances affect the battery, BMS, inverter, cables, protection and charging requirements.

Can You Keep the Existing Mains Charger?

Possibly.

The charger must be identified and checked against the selected battery manufacturer’s charging requirements.

Questions include:

• Does it have a lithium profile?
• What is its absorption voltage?
• Does it use equalisation?
• Can temperature compensation be disabled?
• What is its maximum output?
• Can the battery accept that current?
• Does it support low-temperature shutdown?
• Is it integrated into other motorhome functions?

A charger should not be described as suitable merely because it produces approximately 14V.

The complete charging profile matters.

Can You Keep the Existing Solar Controller?

Again, possibly.

A solar controller may be retained where:

• It supports suitable lithium settings
• Its output is within battery limits
• Its input rating suits the panels
• Equalisation can be disabled
• It provides appropriate temperature behaviour
• Cabling and protection are suitable

Some controllers may only need reconfiguration.

Others may need replacement.

Do You Need a DC-to-DC Charger?

Many modern conversions benefit from one, particularly where:

• The vehicle has a smart alternator
• A high-capacity lithium battery is fitted
• Charging current needs controlling
• The existing split-charge system is unsuitable
• Correct isolation is required
• Long cable runs exist

However, the correct decision depends on the vehicle, alternator, battery and existing system.

A DC-to-DC charger should not be added without checking whether the alternator and vehicle wiring can support its input demand.

Is 100Ah of Lithium Enough?

It may be enough for:

• Weekend use
• Lighting
• Water pump
• Phone charging
• Compressor fridge
• Limited diesel-heater use
• Modest electronics

It may be inadequate for:

• Long winter stays
• Frequent laptop use
• Large inverter
• Electric cooking
• Full-time living
• Several days without charging

Battery capacity should be based on a realistic energy assessment.

List each appliance and estimate:

• Current or wattage
• Daily operating time
• Startup demand
• Seasonal use

Then compare this with:

• Battery capacity
• Solar production
• Alternator charging
• Mains availability
• Desired reserve

Choosing a battery from the physical space available rather than the expected electrical use often leads to disappointment.

Does 100Ah of Lithium Replace 200Ah of AGM?

It can provide a similar amount of practically available energy in some systems, but it is not a universal one-for-two rule.

The real comparison depends on:

• Permitted depth of discharge
• Battery condition
• Discharge current
• Temperature
• Manufacturer limits
• Required reserve
• Appliance shutdown voltage

Lithium batteries are often used more deeply than lead-acid batteries while maintaining a stable voltage, but the selected battery’s specifications and BMS limits still apply.

A proper calculation should compare usable watt-hours, not simply the amp-hour number printed on each case.

Will Lithium Fix a Battery That Keeps Going Flat?

Not necessarily.

A larger or newer battery will not correct:

• Failed solar charging
• Faulty DC-to-DC charger
• Broken mains charger
• Hidden parasitic drain
• Fridge running continuously
• Inverter left on
• Poor connections
• Undersized cables
• Incorrect battery-monitor settings

Before upgrading, identify why the existing battery becomes flat.

Read Why Does My Campervan or Motorhome Leisure Battery Keep Going Flat Overnight? before assuming that additional battery capacity is the solution.

Is a Lithium Battery Upgrade Worth It?

A lithium upgrade is often worthwhile for owners who:

• Regularly camp without hook-up
• Need more usable capacity
• Run a compressor fridge
• Use a diesel heater frequently
• Work remotely from the vehicle
• Want to reduce battery weight
• Need faster charging
• Use an inverter
• Keep the vehicle long-term

It may offer little benefit where the vehicle:

• Is nearly always connected to mains
• Has very low electrical consumption
• Is used only for occasional short trips
• Has an existing healthy battery
• Has limited charging capacity
• Is likely to be sold shortly

The correct upgrade is the smallest system that reliably meets the owner’s actual needs.

Buying the largest battery that fits is not automatically good system design.

Should You Buy a Cheap Lithium Battery?

Price should not be the only consideration.

Check:

• Battery chemistry
• BMS continuous-current rating
• Surge-current rating
• Charge-current limit
• Low-temperature protection
• Bluetooth monitoring
• Physical construction
• Terminal quality
• Warranty
• UK technical support
• Certification
• Manufacturer instructions
• Service and replacement arrangements

A small battery paired with a powerful inverter may be limited by its BMS even when the battery has enough stored energy.

For example, a 2,000W inverter can demand well over 150A from a nominal 12V battery after losses are considered.

The battery, cabling and protection must all support that demand.

Can You Install a Lithium Battery Yourself?

A simple battery swap may look straightforward, but a safe installation requires more than matching positive and negative terminals.

Risks include:

• Short circuit
• Incorrect fuse rating
• Reverse polarity
• Uncontrolled charging current
• Cable overheating
• Unsuitable charger settings
• BMS shutdown
• Damage to vehicle electronics
• Loose battery restraint
• Inaccurate monitoring
• Fire from poor connections

Campervan batteries can deliver very high current into a fault.

Do not attempt the work unless you understand:

• Cable sizing
• Overcurrent protection
• Charging profiles
• Isolation
• Battery manufacturer requirements
• BMS limits
• Safe termination methods
• Vehicle charging systems

What Information Is Needed for a Lithium Upgrade Quote?

To provide a meaningful initial assessment, we normally need:

• Vehicle make, model and year
• Campervan or motorhome type
• Existing battery make and capacity
• Battery location
• Photographs of the battery compartment
• Mains charger make and model
• Solar-controller make and model
• DC-to-DC charger or split-charge system
• Solar-panel capacity
• Inverter make and rating
• Current fuse board
• Intended appliances
• Typical time spent off-grid
• Expected winter use
• Any existing electrical faults

A workshop inspection may still be needed where components cannot be identified from photographs.

Lithium Battery Upgrades in Blackburn

WeConvert provides campervan and motorhome lithium battery installation and electrical upgrades from our Blackburn workshop.

We can assess and install suitable systems involving:

• LiFePO4 leisure batteries
• Battery-management systems
• DC-to-DC chargers
• Mains battery chargers
• Solar charge controllers
• Battery monitors and shunts
• Inverters
• Busbars
• Battery isolators
• Fuses and circuit protection
• Cable upgrades
• Low-temperature charging protection
• Existing self-build installations
• Factory motorhome systems

Our Blackburn workshop serves customers travelling from:

• Blackburn
• Darwen
• Accrington
• Burnley
• Rossendale
• Bolton
• Chorley
• Preston
• Wider Lancashire

Learn more about our campervan electrical and solar services in Blackburn.

Where the current system already has a fault, also see:

• Campervan or Motorhome 12V Electrics Not Working?
• Why Is My Campervan Leisure Battery Not Charging?
• Campervan or Motorhome Solar Panel Not Charging the Battery?
• Campervan or Motorhome Mains Hook-Up Not Working?
• Campervan and Motorhome Repairs and Fault Finding

Frequently Asked Questions

How much does it cost to upgrade a campervan to lithium?

A straightforward 100–150Ah lithium installation may cost around £600–£1,000.

Where chargers, cabling, monitoring and protection also need changing, expect approximately £1,200–£3,000.

Large off-grid systems with powerful inverters can cost £3,500–£6,000 or more.

Can I replace an AGM leisure battery with lithium?

Possibly, but the charging system must be checked first.

The alternator charging, mains charger and solar controller must all be compatible with the selected lithium battery.

Do I need a new charger for a lithium leisure battery?

Not always.

An existing charger may be suitable if its charging profile matches the battery manufacturer’s requirements. Older chargers may need replacing.

Do I need a DC-to-DC charger for lithium?

Many modern vehicles and lithium installations use a DC-to-DC charger to control alternator charging.

Whether one is required depends on the vehicle, alternator, battery and existing wiring.

Can I use my existing solar panels with lithium?

Usually, the panels themselves can remain.

The solar charge controller and its settings need checking for compatibility with the lithium battery.

Is 100Ah of lithium enough for a campervan?

It can be enough for lower-to-moderate electrical use, including lights, water pump, phone charging and a compressor fridge.

Higher consumption, winter use and long off-grid stays may require more capacity.

Can lithium batteries be charged in freezing weather?

Only within the temperature range specified by the battery manufacturer.

Many standard LiFePO4 batteries prevent or prohibit charging around or below 0°C, while some use internal heating or specialist low-temperature cells.

Does lithium work with a diesel heater?

Yes, provided the battery, wiring and charging system are correctly sized.

The heater’s startup current and low-voltage requirements should be considered.

Can a lithium battery run an inverter?

Yes, provided the battery BMS, cables, fuse and inverter are rated for the required current.

Battery capacity alone does not determine whether it can safely power a large inverter.

Does a lithium battery need ventilation?

LiFePO4 batteries do not normally vent during ordinary operation in the same way as flooded lead-acid batteries, but the installation must still comply with the battery manufacturer’s requirements.

The battery should remain protected from heat, water, impact and short circuit.

Will a lithium battery charge faster?

Lithium batteries can often accept higher charging currents than traditional lead-acid batteries, but actual charging speed is limited by the charger, alternator, cables, battery BMS and available energy source.

Can WeConvert upgrade a factory-built motorhome to lithium?

Yes, subject to inspection and system compatibility.

Factory motorhomes may have integrated chargers and control systems that need identifying before a final specification can be provided.

Book a Campervan Lithium Battery Upgrade in Blackburn

To discuss a lithium battery upgrade, send us:

• Vehicle make, model and year
• Photographs of the existing battery
• Existing battery make and capacity
• Charger model numbers
• Solar-panel capacity
• Inverter details
• Appliances you want to operate
• Typical time spent off-grid
• Whether you travel during winter
• Your postcode

We can then advise on a suitable battery capacity and whether the existing charging equipment can be retained.

Contact WeConvert to request a campervan or motorhome lithium battery upgrade in Blackburn.