Veloris Group Ltd blog

What Size Leisure Battery Do I Need? A Sizing Guide

Ben — Fri, 09 Oct 2026 14:08:21 GMT

Buying a leisure battery based on budget alone, or simply matching what came with your caravan or boat, often leads to disappointment down the line. Too small, and you'll be searching for a plug socket halfway through your trip. Too large, and you're paying for capacity you'll never use. So, what size leisure battery do you actually need? It comes down to working out how much power your appliances draw, how long you'll be running them, and how many days you need to go between charges.

Understanding amp-hours

Leisure battery capacity is measured in amp-hours (Ah), which describes how much current a battery can supply over time. A 100Ah battery, for example, can theoretically deliver 100 amps for one hour, or 1 amp for 100 hours, though real-world usage rarely runs a battery down to empty.

It's also worth knowing that different chemistries offer different usable capacity. As a general sizing rule, it's common to allow for around 50% usable capacity from lead-acid or AGM batteries, while LiFePO4 batteries typically allow 80% or more of their rated capacity to be used, depending on the manufacturer. This difference matters enormously when you're sizing a battery, as two batteries with the same rated capacity can offer very different amounts of usable energy.

Calculating your daily power usage

The most reliable way to size a battery is to add up the power draw of everything you plan to run, then work out how long you'll use each item per day.

Start by listing your appliances and their wattage or amp draw, which is usually printed on the appliance itself or in its manual. Multiply the amp draw by the number of hours you'll use it each day to get the amp-hours required for that appliance. Add these figures together across everything you plan to run, from lighting and water pumps to fridges, chargers and entertainment systems, to reach your total daily amp-hour requirement.

From there, decide how many days of autonomy you want, meaning how long you need to run without recharging via mains hook-up, solar or your vehicle's alternator. Multiply your daily usage by the number of days, then divide by your battery's usable capacity percentage to find the battery size you actually need.

A worked example

Let's say a weekend away involves the following daily usage:

LED lighting: 2A for 5 hours = 10Ah
Water pump: 4A for 1 hour = 4Ah
Phone and device charging: 2A for 3 hours = 6Ah
12V fridge: 3A for 24 hours = 72Ah

That totals 92Ah of daily usage. If you want two days of autonomy without recharging, that's 184Ah required in total.

For a lead-acid or AGM setup, where you'd only use around 50% of the rated capacity, you'd need a battery rated at roughly 368Ah to comfortably cover that usage, which in practice would mean two or more batteries wired together. For a lithium setup, where you can safely use around 80% of the rated capacity, a single 230 Ah battery would meet the same requirement with far less bulk and weight.

This is exactly why so many caravan, motorhome and boat owners are moving towards lithium as their power needs grow. It isn't just about a longer lifespan; it's about getting more usable energy from a smaller, lighter unit. If you're powering a boat specifically, our Marine page covers the additional factors, like vibration resistance and onboard charging, worth weighing up alongside sizing.

Other factors to consider

Beyond raw capacity, a few other things affect the right size battery for your setup.

Charging sources matter just as much as the battery itself. If you're relying on solar panels or a vehicle's alternator to top up between uses, your battery needs to be sized so it can be fully replenished within the time available, not just sized to last as long as possible on a single charge. Our Solar Systems page has more on matching panel output to battery capacity if you're planning a solar top-up setup.

Physical space and weight limits can also rule certain sizes out, particularly in smaller caravans, campervans or boats where every kilogram and every centimetre of locker space counts. Lithium's higher energy density often makes it the practical choice when space is tight.

Future-proofing is worth factoring in too. If you're likely to add appliances, upgrade to a bigger fridge, or extend your trips over time, sizing slightly above your current calculated need can save you from having to replace the battery again sooner than expected.

Getting the sizing right from the start

Getting your leisure battery size right from the outset saves money, hassle and the frustration of running out of power at the wrong moment. If you're weighing up capacity, chemistry or which setup suits your usage best, take a look at our Leisure page to find the right battery solution for your application, or get in touch with our team for tailored sizing advice.

Sources and further reading

How Long Does a Leisure Battery Last?

Ben — Wed, 30 Sep 2026 13:52:38 GMT

Do you rely on a leisure battery to keep the lights on, the fridge running or other appliances powered while you are away from home? If so, you will know how frustrating it can be when performance starts to decline.

So, how long does a leisure battery last? As a general guide, a leisure battery can last around three to ten years or more. The exact lifespan depends on the battery chemistry, how often and how deeply it is discharged, how it is charged and how well it is maintained.

Typical lifespan by battery type

Leisure batteries are not all built the same way, and lifespan varies considerably between chemistries.

Lead-acid batteries are one of the most affordable options and will often provide around three to five years of service when used and maintained correctly. Cycle life varies by model and depth of discharge, but repeated deep discharges generally shorten their lifespan.

AGM (Absorbent Glass Mat) batteries are sealed lead-acid batteries designed to cope well with vibration and demanding applications. A typical AGM leisure battery may last around four to seven years, depending on the battery, charging regime and depth of discharge.

Lithium iron phosphate (LiFePO4) batteries generally offer the longest lifespan. Many can provide several thousand charge cycles and may last eight to ten years or longer. They cost more upfront, but their longer cycle life, lower weight and greater usable capacity can make them cost-effective over time.

What shortens a leisure battery's life?

Even a high-quality battery can wear out prematurely if it is regularly pushed beyond its recommended operating conditions.

Deep discharges are particularly hard on lead-acid batteries. Frequently using a large proportion of the battery's capacity can reduce the number of cycles it delivers. Lithium batteries cope with deeper cycling much better, but depth of discharge still affects cycle life, so avoiding unnecessary full discharges can help maximise longevity.

Poor charging habits can also cause damage. Leaving a lead-acid battery partially discharged for long periods can encourage sulphation, where lead sulphate crystals build up on the plates and reduce usable capacity. Persistent overcharging can also damage a battery through excess heat and unwanted chemical reactions.

Using the wrong charger is another common problem. The charger should have a charging profile suitable for the battery chemistry and follow the manufacturer's recommended settings.

Extreme temperatures matter too. Excessive heat accelerates battery ageing, while low temperatures can temporarily reduce performance. Lithium batteries need particular care in cold conditions, as many LiFePO4 batteries should not be charged below their specified minimum charging temperature unless suitable protection or heating is fitted.

Care tips to extend battery life

A few simple habits can help you get more reliable service from your leisure battery.

Avoid leaving the battery discharged for long periods, particularly during winter storage. Follow the manufacturer's storage guidance and check the battery periodically when your caravan, motorhome or boat is not being used.

Match your charger to the battery type. Lead-acid, AGM and LiFePO4 batteries have different charging requirements, so make sure your mains charger, solar controller and DC-to-DC charger are compatible with your battery.

Keep terminals and connections clean and secure. Poor connections can increase resistance and reduce charging efficiency. Periodic checks can also help you spot loose terminals, damaged cables or corrosion early.

Avoid mixing old and new batteries in the same bank unless the manufacturer specifically permits it. Differences in age, capacity and internal resistance can lead to uneven charging and discharging.

It is also worth monitoring the state of charge. A suitable battery monitor can help you understand how much energy you are using and reduce the risk of repeatedly over-discharging the battery.

Getting the right battery for your needs

Battery lifespan starts with choosing the right battery for the job. Whether you are powering a caravan, motorhome or boat, the best option depends on how much energy you use, how often you travel, how you recharge and the space and weight available.

Choosing the right battery chemistry and capacity, then pairing it with a suitable charging system, can make a significant difference to both lifespan and day-to-day reliability.

Take a look at our Leisure page to find the right battery solution for your application, or get in touch with our team for tailored advice on choosing and maintaining the right leisure battery for you.

Sources and Further Reading

VARTA's new technology-based battery portfolio

BDD Marketing — Thu, 10 Apr 2025 11:17:20 GMT

Introducing VARTA's new technology-based battery portfolio—reimagined for today's complex vehicle landscape with a simple colour-coded system:

GOLD: AGM technology for vehicles with highest energy demands

SILVER: EFB for increased energy needs

BLUE: SLI for conventional engines

VARTA's new product portfolio, accompanied by a new colour code, focuses on technologies such as Li-Ion, AGM, EFB and SLI to differentiate and quickly identify the right technology for the right application. Clearly structured, it optimizes the experts' workflow and is easier to manage for our customers.

Greater clarity. Faster processes. Increased efficiency. All with VARTA's premium quality.

Qualified service engineers and national coverage set Veloris apart

BDD Marketing — Tue, 17 Dec 2024 09:58:20 GMT

When important capital equipment such as a forklift is out of action, it ceases to be an asset and becomes a cost, so naturally, the sooner it is back up and running the better.

THIS IS just one of the many ways the Veloris' Industrial Division can benefit businesses in the materials handling industry.

In addition to being the country’s largest battery distributor, enjoying supplier partnerships with brands such as E-Drive, Rolls, Sonnenschein and US Battery, it stands apart from the competition due to its team of experienced service engineers and a 13 branch network stretching from Glasgow down to Fareham and from Witham in the east across to Crumlin, in the west.

This level of truly national converge allows Veloris to respond to the needs of the industry to get valuable working equipment back into service in the shortest possible time, whether it needs a number of new cells or a complete battery tray.

In addition, with the experience inherent within a specialist business that has been trading for more than 70 years, along with the high quality training each engineer undertakes, the company is able to provide its customers with an economical breakdown repair or short term resolution to ensure they have a first fix solution that means that equipment downtime is reduced to an absolute minimum.

Further reducing the load on the shoulders of hard pressed warehouse managers and those operating or responsible for the maintenance of forklifts, Veloris also offers a solution for environmentally friendly battery collection and recycling.

Due to the aforementioned battery supply partnerships, replacement batteries are another mainstay of Veloris' industrial offering. So, whether the need is for a premium quality solution that will last several years and provide a superior return on investment, or for something more basic, the company’s well stocked distribution hubs can deliver a good, better, best option across all battery types from traction to backup power storage.

12-Volt Battery Market Overview

BDD Marketing — Tue, 10 Dec 2024 16:40:18 GMT

Wherever your business might fit within the independent service and repair sector, understanding the shifting sands of any product or product group is important, but as the UK’s largest battery distributor, we are in a particularly strong position to observe the developments, identify the trends and subsequently advise our customers of the direction of travel, when it comes to the 12-volt battery market.

Understanding the market helps you manage your stock more efficiently and allows you to make sure you have at hand the replacement batteries that your workshop customers will require on a daily basis. This in turn ensures that workshops can correctly address the needs of their customers as they bring their vehicles in for service or repair.

Distributing brands that include original equipment manufacturers such as Exide and VARTA, as well as premium quality aftermarket makes like Lucas and Numax, we are able to examine a significant quantity of data, from across the sector, to build a clear picture of the present position and provide a reliable forecast of what the ongoing landscape is likely to look like.

So, how is the market developing?

Historically, up to and even following, the vehicle manufacturer’s (VM) widespread adoption of start/stop technology, traditional SLI (starter, ignition and lights) batteries were the prominent replacement throughout the aftermarket. However, in order to give their respective customers a degree of purchasing choice, workshops would generally provide differentiation to their offerings through a good, better, best option.

As intimated, although the VM’s commitment to start/stop systems prompted a change in the technology provided by the battery manufacturers, who moved away from SLI and over to AGM (absorbent glass mat) and then EFB (enhanced flooded battery), this change wasn’t reflected in the replacement market for several years. In 2016, for example, just 2% of our sales were AGM/EFB, whereas by 2022 it was nearly one quarter, with a comparable decline in SLI sales.

Two years on and the migration to AGM/EFB batteries has continued, cemented all the more as start/stop technology is now fitted to almost every vehicle still incorporating a combustion engine. Ecobat Battery sales data confirms the reality of this trend as the present split between SLI and AGM/EFB is now 64%/36% and, when combined with vehicle application data, the migration rate looks to be accelerating. As a result, it is likely that the battery sales will be split 50%/50% possibly as early as the end of 2025.

What this comparison does not convey, however, is the impact that the shift in technology has had in terms of the life expectancy of these batteries, which are considerably more robust that their SLI cousins. In addition, however, the efficiency of smart charging systems cannot be overlooked.

Rather than simply delivering constant charge solely dependent on the speed of the alternator, these modern systems constantly monitor the condition of the battery through the battery management system, intelligent battery sensor and the electronic control unit, to regulate the alternator to ensure it always receives the most appropriate level of charge.

As a combined result, the evidence suggests that generally, they are lasting 30 to 50% longer than a traditional SLI battery, which points to a decline in overall replacement battery volumes. However, the reduction in quantity is somewhat mitigated by the higher average price of AGM/EFB batteries, so revenue is unlikely to drop to the same extent.

As well as the useful insight that analysing the data gives those selling batteries, another very important aspect of the research is to highlight the importance of fitting a replacement of the correct technology for the application, which is something reflected in original equipment supplier VARTA’s recent decision to dispense with its Black, Blue and Silver hierarchy, in favour of simply offering SLI, EFB or AGM batteries.

What’s the impact of the electric vehicle revolution?

With the industry’s near obsession with everything electric vehicle (EV) related as the market continues to transition from combustion engines to advanced electric drive systems, largely driven by evolving EU regulations reshaping the market, it is important to restate that the 12-volt battery remains an integral part of every passenger car and van currently in production. This is further endorsed by leading original equipment (OE) manufacturer, Exide Technologies, which has stated that ‘the 12-volt lead-acid battery is the crucial energy source in e-mobility that keeps everything running’.

It is, therefore, difficult to overemphasise the role of the12-volt battery, because it is responsible for so many things, in fact almost nothing works without it. In an EV, for example, it provides the energy necessary to activate the safety relay and connect the high-voltage battery to the electrical board net and electric motor, and as ADAS (advanced driver assistance systems) and AV (autonomous driving) continue to evolve, the 12-volt system is increasingly important to ensure reliability and safety, whatever the propulsion system the vehicle uses.

So, as the number of hybrid and EVs is only going to increase, you need to be sure that you have access to not only the correct specification replacements, but also those of the appropriate quality to provide a safe and reliable solution for your customers, whether professional workshops or DIY enthusiasts. Fortunately, through Veloris, you have immediate access to several suitable alternatives with OE brands such as Exide and VARTA and premium quality aftermarket products in Lucas and Numax.

What might also come as another surprise is the fact that not every contemporary hybrid and EV is fitted with the latest 12-volt battery technology. Although it would be natural to make the immediate assumption that these batteries would be at a minimum AGM (absorbent glass mat), if not lithium, the truth is that there is no ‘standard’ battery for these applications, with vehicle manufacturers using a number of different solutions.

There is no better example of this paradox than looking at models such as the 2021 Hyundai Ioniq 5, the 2023 KIA e-Niro, the Audi Q4 e-tron and the Jaguar I-Pace, all of which use a traditional lead acid battery, whereas a Cupra Born uses an EFB (enhanced flooded battery) and a Ford Mustang Mach-E has an AGM!

Another anomaly is that as well as relying on a variety of technologies, there is also a wide range of case sizes and terminal configurations, which can be appreciated when highlighting Exide’s latest EK013. With a capacity of only 1.2 Ah and measuring just 97mm long, 43mm wide and 58mm tall, it supports automatic drivetrain electronics and gearbox electric oil pumps, playing a critical role in ensuring that vehicles continue to operate smoothly and reliably in the event of a malfunction with the main 12-volt batteries.

A Lucas version, LSLA1.2-12, is also available, and both provide coverage for more than five million vehicles across Europe, including the Range Rover Evoque L538 series (OE part number 19G207C-AA), Mercedes Benz A class (W177, V177), B class (W242, W246, W247), CLA (C117, C118, X117), CLS (C218, X218), E class (W212, S212), EQA/EQB/EQE/EQV, G class (W463), GL class (X164, X166), GLA (H247, X156), GLB (X247), GLE (W166, C292), GLK (X204, GLS (X166), M class (W164), R class (W251, V251), S class (W221), Sprinter (B907, B910), V class (W447), (OE part number N000000004039).

For further details, please visit Ecobat Battery at: Cars & Small Vans

Lucas are sponsoring Paul Barker, who’s racing in this year's British Superstock 1000 Series

BDD Marketing — Mon, 11 Nov 2024 15:39:24 GMT

12 Rounds Taking Place This Year

The British Superstock 1000 Series is taking place across the UK. This prestigious tournament gives riders the chance to compete on motorcycles that are shop-bought and modified to racing specifications.

The championship started at Oulton Park, in Cheshire, back in May and will finish at Brands Hatch in October. The 12 rounds will sit alongside the UK rounds of the British Super Bike Championships with an additional round at Silverstone on the 3rd and 4th August. Each event attracts between 35-600 spectators with millions more watching the races on TV.

About Paul

Paul Barker is 44 and has been racing for since 2009. He’s been a No Limits Championship contestant for many years.

Paul will be competing on a Honda Fireblade RRR 2023 superstock which is capable of reaching well over 180 mph. The bike can get up to 60mph in 2.9 seconds, 130mph in 7.2 seconds and can cover a quarter of a mile in roughly 9.8 seconds. With 207hp, this motorcycle is more powerful than an average family car.

Tough Competition

This series draws in top riders from the UK. Paul will be competing against the likes of Davey Todd who has just returned from winning the Isle of Man Senior TT. Other renowned names include John McGuiness who has 23 TT wins and Micheal Dunlop who’s won the TT 25 times.

Lucas Motorcycle Batteries

Veloris became the official licence holder for Lucas in 2025. Lucas Motorsport batteries include Standard, AGM Liquifix, AGM VRLA and Gel.

Suitable for motorcycles, off-road vehicles and jet-skis, Lucas batteries have exceptional starting power, up to 30% more than traditional batteries. Designed to withstand repeated discharge and give exceptional starting power.

Locomotive success for Sheffield University Team!

BDD Marketing — Mon, 11 Nov 2024 14:44:29 GMT

Providing Numax Batteries to Engineering Students at the University of Sheffield.

The IMechE Railway Challenge 2024

June saw great success from the University of Sheffield Railway Challenge team, after they won the IMechE Railway Challenge 2024! The IMechE Railway Challenge is a competition held every June, where engineering students from all over the world are challenged to build a small-scale working train. The challenge annually begins in October and the final event is June/July the following year which this year was held at the Stapleford Miniature Railway in Leicestershire. Amongst the teams, there were Mechanical Engineering Students, Graduates and Apprentices all working in the field. The Sheffield team has approximately thirty undergraduate students from across engineering disciplines. Participants must design and produce a miniature railway locomotive following the precise rules and technical regulations from the board. The design, manufacturing and testing phases provide individuals with a comprehensive understanding of the engineering process. By collaborating in teams, they also foster a development of essential personal skills including finance, communications, management and planning.

Numax Leisure Batteries

Veloris proudly sponsored the team with the support from our East and South East Business Development Manager, Mark Allsopp. Our lead acid batteries powered the heart of their locomotive, fuelling innovation and sustainability. We donated 4 x Numax XV31 batteries and a Victron Charger. Veloris provides battery systems and solutions for a variety of railway vehicles to the modern rail industry. Choosing the correct leisure battery is all about understanding your power usage. The Numax leisure range covers all situations, applications and levels of power usage depending on what you need from your battery. Leisure batteries are not simple “black boxes”. The design and materials used to play a decisive role when determining the life span and durability of the cells. The XV range are heavy-duty dual-purpose leisure batteries designed for starting and deep cycle. Marketing Co-ordinator Will, shared 'A huge factor us winning this year was us using new Veloris, since last year we lost a lot of points in this category due to battery failure.'

The Winning Team

As well as winning the overall competition, the team also won in several other categories:

Auto-Coupler Challenge
Remote Data Monitoring
Location Announcement
Auto-Stop Challenge
Innovation Challenge
Reliability Challenge

Why do 12V batteries cause EV breakdowns?

BDD Marketing — Mon, 11 Nov 2024 13:27:33 GMT

Following its recent findings concerning the ongoing demand for 12V batteries, Veloris has released further data for this long-term aftermarket requirement, following research into EV breakdown statistics.

As previously made clear, whether an EV incorporates an ICE with a 48V or 350V battery in hybrid form or uses a 400V plus battery as a fully battery powered variant, a ‘traditional’ 12V battery is also fitted.

The revelation comes, however, in the fact that in common with their ICE powered counterparts, the number one cause of EV breakdown also turns out to be failure of this battery! But why?

Since the UK launch of the Tesla a decade ago, and following changes in government legislation, many other VMs have added full EVs to their product ranges.

As a result, they and their partners have invested hundreds of millions of pounds to develop the electric motors, control systems and high voltage (HV) battery packs to make the move from relying on an ICE, to using fully electric propulsion achievable.

However, as stated previously, in the quest to develop these new technology vehicles, not everything is new, as 12V systems remain integral to EVs to enable them to perform vital functions. These include not only powering the lighting system, both internal and external, but the central locking, alarm, and other security features. It also powers the vehicles onboard computer and diagnostic systems and plays a role in starting the main HV battery pack.

In vehicles with ICEs, the electrical system relies on the alternator to recharge the 12V battery after providing energy to start the engine. This process, refined over years, is managed by the vehicle’s ECUs; however, in EVs, the 12V battery plays a more cyclical role. It is charged by the HV battery and discharged by the various 12V systems, placing significant load on it.

Irrespective of whether the vehicle is an EV or incorporates an ICE, the maintenance of its 12V battery is down to the parameters set in the ECU’s battery management system.

It’s well known that discharging a standard 12V SLI (starter, ignition and lighting) battery beyond 50% will reduce its life expectancy; however, largely due to the fact that range anxiety is one of the key barriers to EV uptake, VMs want to maximise the range capability that they can offer drivers. To do this, the battery management system has to make a compromise between charging the 12V battery to keep it in top condition, or providing for the vehicle’s optimum range, which can result in an undercharged 12V battery, affecting its usable life.

A further impact on the life of the 12V battery comes with the advanced technology inbuilt into an EV. Its inherent connectivity and the plethora of apps it can run, such as to remotely ‘wake it up’ and activate the 12V system, for example, can require 5,000 activations per day, which can seriously discharge the 12V battery and leave the driver with a lifeless car.

Opportunities arise

Although the VMs work hard to update their systems when they find these issues, in the meantime they provide a welcome opportunity for the aftermarket because, despite many workshops being wary of working on EVs, it should be encouraging for them to know that the most likely cause of a breakdown is due to one of the components that they are most familiar with!

Therefore, before your workshop customers surrender an EV to the franchised dealer network, they should first assess the condition of the 12V battery and if that’s the issue, providing they use the correct protocols for working on a HV vehicle, installing a replacement not only solves a problem for the owner, but it also makes a profitable job.

Conclusion

As a result of its findings and to further assist the independent service and repair sector, Veloris has updated its application data on its online Battery Finder, as well as its Numax and Lucas data on MAM Autocat, to provide all the necessary application links to these vehicles.