Prioritising Safety on the Road

Why a Quality Battery with a BMS (Battery Management System) is a Must

by Wayne Hunt

Living the motorhome life, I’ve come to appreciate the freedom, the open road, and yes, even the unexpected situations that it brings. But what about when the unexpected involves your motorhome’s power system?

I had a firsthand experience that brought this home for me.

I was recently helping some friends – who shall remain nameless to protect the guilty – navigate an unexpected situation. These folks have quality lithium batteries and an inverter charger.

They were plugged into power, running a 2Kw heater and brewing a hot cuppa with a 2.2Kw jug when pop went the circuit breaker on the board they were plugged into. In a bit of a hurry and without thinking or checking, they tried to restart their appliances. Only now, they weren’t on mains and were running off their 2000VA inverter charger, which was suddenly being asked to deliver well over its maximum load.

Under normal circumstances, I would have expected the inverter charger to shut down on overload. But in their case, they were also exceeding the maximum discharge rate of their two LiFeP04 batteries. What massively impressed me was the Battery Management System (BMS) in their ALLiON batteries. It detected the overload and swiftly shut the batteries down before the inverter charger had a chance to shut down on overload.

This is a textbook example of the kind of innocent overload that can either blow fuses, or worse, damage hardware on lesser quality gear! But thankfully, because of the quality BMS in their batteries, disaster was averted. This brings me to the heart of your motorhome’s power system: lithium iron phosphate batteries and inverter chargers. These are the unsung heroes that keep our lights on, our food cold, and our kettles boiling. But just like any hero, they need a safeguard – that’s where a Battery Management System (BMS) steps in.

A BMS is like a trusty sidekick for your battery. It’s there to protect the battery , and provide protection from overloads, over voltage and over discharge It’s the quiet overseer ensuring your motorhome’s power keeps ticking along without a hitch.

In this particulary story, the couple’s ALLiON batteries’ BMS detected the overload and swiftly shut the batteries down, saving them from potential damage. But it’s worth noting that not all batteries have such a dependable sidekick. Cheaper options often skip this critical feature, leaving them vulnerable to overloads and the safety risks that follow.

That’s why I can’t stress enough the value of investing in a quality battery with a robust BMS, like our ALLiON range. It’s not just about upfront costs, but about considering the potential expense of replacing damaged equipment or dealing with a safety incident. The peace of mind a good BMS offers is priceless.

So, to wrap up, a quality Battery Management System is an essential ally for your motorhome’s power setup. It keeps your LiFeP04 batteries, the most expensive elements of your solar power system, running safely and efficiently, shielding them from overloads and ensuring they live a long, productive life.

All of the batteries sold by Motorhome Solar are equipped with a reliable BMS. We’re all about empowering you to make informed decisions, and ensuring your motorhome adventures are powered safely.

A Closer Look: Exploring the Functions of a BMS

A BMS is not just a protector, but it’s also like the brain of a battery, intelligently managing its operation under various circumstances. Let’s delve a bit deeper into its key functions:

Charge Regulation:

A BMS monitors and controls the charging process to make sure each cell in a battery pack is charged in the correct manner and remains balanced.

Discharge Regulation:

Similarly, during discharging or use, the BMS ensures that the battery doesn’t discharge above a preset current limit which could otherwise damage the battery and reduce its lifespan.

Voltage Monitoring:

Each cell in a battery pack has a specific voltage range within which it should operate. The BMS continuously monitors the voltage of each cell and intervenes, generally at the top of the charge cycle if any cell goes outside this range. This function helps to prevent damage and extend the life of the battery.

Temperature Monitoring:

Batteries are sensitive to temperature variations. They can get damaged if charged under extreme temperatures. A BMS can keep track of the battery temperature and if it detects a temperature that’s too high or too low, it can cut off power to protect the battery.


Lithium does not balance naturally in the same way lead batteries do. A BMS works to ensure that the cells within a battery are evenly charged, a process known as balancing. This helps to maximise the capacity and lifespan of the battery.


Many BMS systems can communicate with external devices to provide information about the battery’s state of charge, health, and other data. This can be useful for monitoring the performance of the battery and diagnosing any issues.

By performing these functions, a BMS plays a pivotal role in the safe and efficient operation of a lithium iron phosphate battery. It helps to extend the life of the battery, prevent potential safety issues, and ensures optimal performance under various conditions.

It should be noted that not all BMSs have the same functionality, so you should always ask, when buying LiFeP04.

Ready for a safer, more efficient motorhome power system?

At Motorhome Solar, we’re committed to providing you with the best in battery technology, including our trusted range which are all equipped with robust BMSs.

We’re here to help you make an informed decision that safeguards your adventurous lifestyle and powers it in the most sustainable way. To learn more about our range of batteries or to upgrade to a safer, more efficient power system, get in touch with us.