Best AGM Leisure Battery UK
At Off Grid Power Geek, we’re always interested in batteries, keeping abreast of the market, developments and what’s going on.
Today, we’re giving you the lowdown on the Best AGM Leisure Battery UK.
AGM batteries are popular for leisure purposes, they do have a lot of big advantages over traditional flooded (wet) batteries. Admittedly, they have some weaknesses in comparison to Lithium (LiFePO4), but they’re cheaper than those.
We’ll let you know which are the best AGM batteries on the market, and also which ones might suit you depending on your needs. And we’ll let you know exactly what you’ll get with AGM batteries in general, and why they’re so superior to a flooded battery.
The Platinum AGM Plus (check price and specs on Amazon) is the winner, and in second place is the SuperBatt AGM1100 (see on Amazon).
Without further ado, let’s get on with it!
Introducing the Best AGM Leisure Battery UK
Let’s take a look then at the best the market has to offer for AGM batteries in 2022.
AGM batteries offer many significant advantages over traditional flooded lead acid batteries. They effectively fix a lot of the weaknesses that have plagued flooded (wet) batteries for many years now, particularly for leisure batteries.
A note on Lithium batteries
Lithium leisure batteries (LiFePO4) have tipped – by which we mean they’re now much more cost effective than lead-acid batteries, and by a distance. They’re still an investment, but less so than before.
We’ve gone in-depth on leisure batteries for motorhomes, campervans and caravans and they beat lead-acid batteries in every measure.
1) Platinum AGM Plus Leisure Battery
Platinum brand batteries are well thought of
The Off Grid Power Geek team has our ear to the ground, and we know they’re of solid repute, supplying major automotive and industrial companies.
Platinum is the top-selling battery brand in the UK.
They’re also a British company.
NCC Verified Class A
The NCC are an independent organization that uphold best standards in the caravan/motorhome/campervan industry. They ensure products offered to people in this industry are the best quality.
Class A batteries have very high storage capacity; they’re best for people who spend a lot of time off grid. It’s for users who need to power motor movers, TVs, microwaves, heaters and other power hungry devices.
Class B, meanwhile is for users who’ll spend most of the time hooked up to a mains supply, but still need to power things like motor movers, on occasion. And they’ll provide enough capacity power for lighting and other light electrical usage. Class C have low capacity, therefore the user only needs very occasional power usage away from the electrical hook up power.
The Platinum AGM Plus Leisure Battery is Class A.
Pricing
It’s more than you’d pay for a similarly sized traditional lead-acid battery, for sure.
But not that much more. Though Platinum don’t offer a cycle life, we know that this type of AGM will likely do at least 500 cycles. And since Platinum are a good maker with good quality cell material, you can expect as much as 700 cycles, at 50% DoD. That’s our estimate, mind.
Bear in mind also, that you can discharge this AGM battery to 70% DoD without damaging it (we wouldn’t go much beyond that, though.
So when you consider 1) it has longer life cycle and 2) how much better it can cope with higher discharge; our bet is that this battery will last as much as twice as long as an equivalent normal lead acid battery.
If it’s the one for you…
Check it out here.
2) SuperBatt AGM1100 12V 120Ah AGM Leisure Battery
Capacity and Cycle Life
At 120Ah capacity, it’s got fully 20Ah more capacity than the Platinum battery.
Given that both are high-quality AGM batteries, you can quite comfortably discharge them to around 70% without harming. That’s a lot better than traditional lead acid batteries, which will be damaged if you discharge them above 50% too often!
To make your battery last as long as possible, you’ll want to discharge it to around 70% and not go beyond that too often.
By our calculations then, you’ll get 14Ah more usable capacity with each cycle with the SuperBatt battery than you would with the Platinum battery.
SuperBatt are a manufacturer with a very solid reputation
Their batteries are probably the AGM leisure batteries with the best reputation for quality in the UK.
Specially designed for Leisure applications
SuperBatt, as a major manufacturer, have high quality manufacturing processes.
The SuperBatt AGM battery is true deep cycle. That means the battery plates are engineered specifically for sustained discharge and charge cycles.
It’s not NCC verified
That doesn’t necessarily mean they’re not equally good quality batteries as the Platinum AGM Plus battery; it just means the makers haven’t submitted their battery for the NCC’s approval.
Pricing is quite low
For a high-quality AGM battery, with good cyclic durability and low self-discharge, this price is as good as it gets.
Where can you get it?
Check it out right here.
AGM Leisure Batteries
If we were talking about car batteries, we’d say AGM batteries are better than traditional lead-acid batteries, for a few reasons.
We’re talking about Leisure batteries, though.
And for Leisure batteries, AGM batteries are a lot better than traditional lead-acid batteries, for multitudinous reasons!
That’s because “normal” lead acid batteries are actually poorly equipped for leisure purposes. They’re designed to provide a large burst of power to start a vehicle engine.
Even now, lead acid leisure batteries are still used for motorhomes, caravans, campervans, RVs etc. But now that you can get an AGM Leisure battery for not that much higher a price than a lead acid leisure battery, it’s a simple decision to choose an AGM battery.
Let’s go into more detail on why AGM batteries are so much better than lead acid batteries.
Why Are AGM Leisure Batteries Superior to Lead Acid?
All lead acid batteries (including AGM and Gel batteries) are able to store charge and deliver power due to the reaction between the Lead plates and the electrolyte (a solution of sulphuric acid and distilled water) inside the battery.
AGM stands for Absorbed Glass Mat. That’s because the electrolyte (the mixture of sulphuric acid and distilled water) is absorbed in fibreglass mats, which are contact with the lead plates.
That’s unlike traditional lead-acid batteries, their electrolyte is in free-flowing, liquid form, which moves around the battery, in contact with the battery’s lead plates, just as any liquid inside an outer casing would.
The AGM technology allows for a much improved internal structure to the battery, resulting in the following advantages.
They can deliver more power
AGM batteries allow for far better use of space inside them. While standard lead acid batteries need lots of room for the liquid electrolyte, with AGM batteries the electrolyte is absorbed on glass mats, so it takes up less room.
Therefore, you get more reaction surface area with AGM batteries, and more reactions means higher energy density. And that means greater ability to store charge and deliver more power.
They can sustainably deliver power for longer
It’s never recommended to discharge standard lead acid batteries above 50% Depth of Discharge (DoD). If you do this regularly, it’s damaging the battery and the battery’s lifespan will be short.
Quality AGM batteries, such as those in this article, however, can hope much better with higher discharge, even up to 70-75%.
That means if you have a 100Ah lead acid battery you should only ever use 50Ah per cycle, and then you should recharge.
With a 100Ah AGM battery, you can use 70Ah of power, without causing any harm to the battery.
When you consider that 1) you can use much more power for each cycle and that 2) AGM batteries deliver many more cycles, perhaps, double, it’s easy to see that over the course of its lifespan, you’ll get far, far more power out of an AGM battery.
Don’t know what size of leisure battery you need? Here’s how to work out how many Ah you need in a leisure battery.
They’re more robust to high discharge
Due to the nature of its internal structure, with free flowing electrolyte, traditional lead acid batteries are easily damaged if you over-discharge them. And as we mentioned, even going over 50% DoD is too much discharge for this type of battery.
Due to their absorbed glass mats and their plate structure, AGM batteries can cope better with higher levels of discharge. It’s not as easily damaged if you do discharge it too much sometimes.
As with any lead-acid battery though, discharging too high too often will still damage even an AGM battery.
Greater cyclic durability (better able to handle sustained and changeable charge and discharge cycles)
Leisure batteries go through very changeable cycles – such as sustained low power when you’re just using lights in the caravan; then perhaps a surge of power if you’re using a motor mover, for example; then some charge when you’re at a campsite with EHU (Electrical Hook Up); then perhaps several weeks out of use entirely.
The above is really not what a standard lead-acid battery wants. It wants regular discharge to exactly 50%, then immediate recharge. And that recharge better be full, and at a high enough voltage. And then the process should start again.
Now when is that ever going to happen with a leisure battery?!
AGM batteries were designed to deal with the more fragmented charge cycles that are, well, reality. Their more tightly packed battery plates allow for greater pack pressure. And this means less active material paste shedding. This, combined with the greater energy density within the plates, make them better equipped for such charge cycles.
Longer lifespan
We mentioned that AGM batteries can withstand higher pack pressure, which means less shedding of the active material (all lead plates have an active material on them which will naturally shed over time).
The shedding of the paste material on battery plates is one of the reasons all lead acid batteries eventually fail – since this happens significantly less with AGM batteries, it’s one of the reasons that AGM batteries will last longer.
Another major reason for their longer lifespan is…
More resistant to sulfation
Sulfation is the No.1 killer of all lead acid batteries, and by a distance. It’s when lead sulfate crystals build up on the battery plates, blocking the amount of charge the battery can store, and hence lessening the power it can deliver. It grows over time, until finally the battery is completely dead.
AGM batteries, like all lead-acid batteries, do develop sulfation on their lead plates. But because of the electrolyte being absorbed on glass mats, it doesn’t happen so severely as when the electrolyte is a liquid.
As a result, sulfation is slower to build up on AGM batteries and therefore, the battery will last longer. Since sulfation also reduces the power of the battery over time, it means AGM batteries will also deliver more power.
More resistant to vibration
The durability of AGM batteries to withstand higher pack pressures also makes them far better equipped to deal with shock and vibration.
Traditional Flooded lead acid batteries degrade internally over time, and even more so if the vehicle is on rough terrain. AGM batteries are made of tougher stuff and can withstand a lot more.
No acid stratification, at all
Acid stratification is when the electrolyte becomes poorly mixed, so there ends up being more acid near the bottom of the battery and more water near the top. That’s because the sulphuric acid has higher density than water.
See the below picture, illustrating this situation.
Lead acid batteries need the reaction between their lead plates and the properly mixed electrolyte to be able to store charge and deliver power.
In a stratified (suffering from acid stratification) battery, the chemical reactions will only be taking place in the middle of the battery, where the electrolyte is well mixed, and less so at the top and bottom of the battery.
With AGM batteries, the electrolyte is not in liquid form, and so it’s impossible for it to become poorly mixed. Therefore, there is no stratification in an AGM battery, at all.
A note on Lithium batteries
Lithium batteries (LiFePO4) have tipped – by which we mean they’re now much more cost effective than lead-acid batteries, and by a distance. They’re still an investment, but less so than before.
Summarising the Best AGM Leisure Battery UK
Hopefully, this article has allowed you to pick the best AGM leisure battery, UK, for you.
The two models we mention, the Platinum AGM Plus (see price on Amazon) and the SuperBatt AGM1100 (check pricing and specifications on Amazon), are the best on the market today, in 2024.
As you’ve read, AGM batteries have some really significant advantages over traditional flooded lead-acid batteries, and you’ll certainly get more sustained power, and over a much longer time.
They’re more resistant to two of the major lead acid battery killers – active material paste shedding and sulfation. And they’re completely resistant to a third killer, acid stratification. It’s simple to see why AGM batteries last so much longer.