Campervan Electrical Upgrades: What to Add and in What Order

Whether you are starting from scratch or improving an existing system, the order in which you make upgrades matters. Some upgrades unlock others; some are wasted money if the foundation is not right first.

The upgrade order that makes sense

Foundation level: get this right first

1. LiFePO4 leisure battery (if you have AGM)

The single most impactful upgrade. Doubles usable capacity, dramatically extends cycle life, and enables faster charging from all sources. Everything else in the system performs better with LiFePO4.

If upgrading: also reconfigure your MPPT and DC-DC charger at the same time.

2. Battery monitor (Victron BMV-712 or SmartShunt)

You cannot manage what you cannot measure. A proper battery monitor that tracks Ah in and out is essential for understanding how your system actually behaves. Install this early — it reveals whether every subsequent upgrade is working.

3. Correct MPPT charge controller (if you have PWM or wrong settings)

A cheap PWM controller or an MPPT set to wrong voltage profiles is leaving significant capacity on the table. Replacing with a correctly configured Victron SmartSolar MPPT can recover 20–30% more usable energy from existing panels.

Charging upgrades: more energy in

4. Add more solar (if undersized)

More panels are the easiest path to more energy in most UK builds. If your battery often runs low in summer, add panels. If you are already solar-saturated in summer but suffer in winter, panels alone will not solve winter shortage — but they are still the cheapest energy source.

Rule of thumb: if your battery reaches full charge before midday in summer, you have enough panels. If it rarely gets above 80%, add more.

5. DC-DC charger (if you use a relay or have none)

A DC-DC charger correctly charges LiFePO4 from the alternator and delivers more charge per hour of driving than a relay. If you drive regularly, this is an important upgrade for full days off-grid.

6. Mains charger or inverter-charger (if you camp at hook-up)

If you regularly use campsites with electric hook-up but do not have a mains charger, you are leaving free energy on the table. A Victron Blue Smart charger is one of the highest-return upgrades for campsite users.

Power out upgrades: more capability

7. Larger or better inverter

If you currently have no inverter and want to run AC appliances, any quality pure sine wave inverter is a significant capability upgrade. If you have a small inverter (under 500W) and want to run a kettle or induction hob, upgrading to 1,000–2,000W opens those options.

8. Upgrading to an inverter-charger (Victron MultiPlus)

An inverter-charger combines inverter + mains charger + automatic changeover (mains to battery) in one unit. If you have a separate inverter and mains charger, replacing both with a MultiPlus simplifies wiring and enables power assist (using battery to supplement a limited hook-up supply).

This is a significant investment (£600–1,500) but appropriate for a full-time build.

Optimisation upgrades

9. Victron network integration (VE.Smart, Cerbo GX)

If you have multiple Victron components, connecting them via VE.Smart Bluetooth network allows the MPPT and DC-DC charger to share battery voltage and temperature data, optimising charging across all sources. A Cerbo GX adds a monitoring display and remote monitoring via Victron VRM.

10. Additional battery capacity

Adding a second battery (or replacing with a larger one) extends autonomy. Only do this if:

• Your solar and charging are already correctly sized
• You regularly run the battery low before recharging
• You have confirmed the charge sources can recharge the larger bank in reasonable time

More battery without more charging just means you can deplete more deeply before you are stuck.

What not to upgrade first

Do not add more solar before upgrading the battery: Solar energy hitting a full AGM battery at 9am is wasted. Fix the battery first, then the panels make more difference.

Do not add a large inverter before correct fusing: An undersized fuse on an inverter cable is a fire risk. Fusing must be upgraded before the inverter.

Do not upgrade the inverter before the battery: A 2,000W inverter on a 100Ah AGM battery is impractical — the battery cannot sustain the load without severe voltage sag. Battery first.

FAQ

I have a 100W panel and 100Ah AGM. What is the best first upgrade?

Replace the AGM with a 100Ah LiFePO4. Your usable capacity doubles (from 50Ah to 90Ah), your existing 100W panel now delivers relatively more because the battery can accept it faster, and your existing DC-DC charger (if correctly configured) charges the new battery more efficiently. This single change transforms the system.

Is upgrading to Victron worth the premium?

For long-term full-time van life, yes — the integration, Bluetooth monitoring, quality, and cycle life make Victron worth it over budget alternatives. For occasional weekend use, a budget MPPT and a good leisure battery is sufficient.

Can I upgrade component by component or do I need to replace everything at once?

Component by component is fine. The only constraint is compatibility: if you replace an AGM with LiFePO4, you must also reconfigure all charge controllers at the same time (not an expensive change — just settings).