The technology used to make batteries has come a long way, and it is no longer what it used to be – especially when the first ones heavily featured wooden encasements and glass cells. Today, there is plenty of specialized technology, as seen in this deep cycle battery vs. AGM.
The rise of different technology in making batteries leads to the rise of different types, which means that there is plenty of confusion among users about what type is best for something.
Many users will also assume that the types are the same, yet further research into this misconception reveals that these types are very different.
What are the differences between the deep cycle and AGM batteries?
| Deep cycle | AGM batteries | |
| Approx. battery weight range (lbs.) | 27 to 40 | 30 |
| Reserve capacity range (in minutes) | 140 | 100 |
| Check here | Check here |
Deep cycle vs. AGM – how these two compare
People who own RVs or boats might be familiar with deep cycle batteries, as they require much more than other types of batteries. These types are also common for golf carts and solar systems.
Both are also lead-acid (except for some cases of deep cycle batteries), and they have a similar approach to their working mechanism. All batteries will have these two slopes, which will then determine the other battery specs:
- CCA, or cold cranking amps, are the number of amps the battery can produce at 0OC or 32OF at a voltage of 10.5V.
- RC or Reserve Capacity – the number of minutes the battery can give out 25A, at a voltage of 10.5V.
When examining these two battery types, you will notice that they do not have many differences since AGM batteries can be considered a type of deep cycle battery in many cases.
However, when looking at their differences, the following observations come through:
Capacity for discharge
AGM batteries are great at handling spillage issues like deep cycle discharge ones. However, the discharge capacity is slightly different for each case, as not all AGM batteries can handle deep discharge similarly.
Deep cycle batteries have thick plates, allowing for deeper discharge without the risk of damage.
The usual case is that the CCAs of a deep cycle battery, especially the LiFePO4 options, will be higher than typical AGM batteries, though the difference is not as great.
In addition, a deep cycle battery can handle several totals or nearly total discharges without suffering damage – but you will need to see whether the AGM battery can handle it before doing it.
Discharge rates
Generally, deep-cycle batteries will have lower discharge rates (especially for the Lithium-ion and gel types), at least when compared to a typical AGM battery.
To know the discharge rate, the manufacturer will indicate the cold cranking amps of the batteries on the sheets containing the specs.
The CCA rating gives you plenty of information to work with, as the higher ones will allow for powering high-energy motors when starting engines.
However, having a battery for solar and UPS use will require those with a lower CCA and higher discharge rate, which is where AGM batteries may fall in.
Note that surge loads are not necessarily as important when choosing the specific battery, though, as the loads are very similar for both AGM and deep cycle types.
Operation
Both batteries will take on different ways of optimizing their working mechanism. AGM batteries aim to give you a large current supply but for a shorter period than the deep cycle battery that spreads out its current delivery over a long time.
Deep cycle vs. AGM – a comparison review
Deep cycle battery – Overview and key features
Unlike traditional batteries, deep cycle batteries are primarily meant for nearly complete discharge regularly, without the extent of suffering damage. They use the same form factor as an auto battery but deliver greater current amounts over a longer period.
There are many types of GAM batteries, and what probably adds to the confusion is that AGM batteries are normally classified as deep cycle types, but not all deep cycle types are AGM batteries. The different types are:
Calcium
This type uses calcium in place of antimony for the battery plates. Because of this, it has several advantages, which include increased corrosion resistance, prevention of gassing problems, lower self-discharge rates, and less water usage in topping up the battery.
It works best for under-bonnet dual battery systems. Note that if you are using it for situations requiring you to discharge it deeply, it is always best to have a charger with a charging mode comprised of calcium to make the most from the battery.
AGM
This is the most common when it comes to auxiliary battery systems. As we will explain in the section on AGM batteries, this uses a fiberglass mat sandwiched between the internal plates and acts as a sponge to prevent acid spillage.
Lead crystal
These are probably the most recent form of the deep cycle battery, having come to the scene in 2009. They are unique, as the technology they use is patented and advanced.
Instead of the traditional lead acid that a conventional battery uses, they use a composite electrolyte of silica (SiO2).
Lithium-ion
This is probably the lightest battery solution in terms of its weight and is the safest form of Lithium battery as it uses LiFePO4 (lithium-iron-phosphate).
These battery types can have greater useable power by up to 60% more than the conventional battery, and they also are 30% more compact and 50% lighter than other batteries, making it a great option if you want to save space and weight.
You can explore some great options for deep-cycle batteries, and they include:
Lifeline marine battery
This is the choice if you want a reliable option of deep cycle battery that supports your marine operations during times of low amperage. You can be assured of its quality, as it meets the strict specifications of the U.S. Coast Guard and Military.
Battle Born LiFePO4 battery
This is a great AGM choice to have around. Its cycle life is also impressive, having between 3000 and 5000 cycles and a full replacement warranty of 3 years.
What we like
- They have a high depth of discharge and a steady power supply
- Recharge quite fast compared to the traditional battery
- Durable and reliable build
What we do not like
- More expensive than other battery options
- Less output of specific energy
What can you see with deep-cycle batteries?
- You will not see many issues with electrolyte spills
- Come in different types, and the choice depends on various factors
- Maintenance-free, except in certain types
- Deep discharge is not an issue for them
AGM battery – Overview and key features
AGM technology stands for the Absorbent Glass Mat, which might sound very strange when you first hear the term but makes sense when you look into its structure.
Instead of taking the traditional battery approach that uses lead plates to react with the acid, this one will use a fiberglass mat that absorbs the sulfuric acid instead of letting it spill out. This results in them becoming spill-proof.
These batteries are called SLA (Sealed Lead Acid) or VRLA (Valve Regulated Lead Acid) types. The technology used to make them is fairly recent, first appearing in the mid-1980s.
They quickly became popular because of their lighter weight compared to most battery types and the fewer hazards involved when handling them, which proved to be very useful for both aircraft and cars alike.
They allowed more users to transport the batteries easily without the dangers of leaking. The fiberglass mat also allowed changes in the battery design to take on a cylindrical form instead of a rectangular design.
Another difference is the smaller acid amounts compared to traditional batteries, which the fiberglass mat will absorb even when the battery breaks.
Varieties of AGM brands
There are some varieties of AGM brands in the market, which include the following:
XS Series Power D3400 AGM battery
This will work for you if you own a racing car, as the electrical resistance levels are quite low, and it is easy to mount in various positions as it is resistant to vibration and spillage.
Optima RedTop 8020-164 35
If you want a tough riding battery, this is probably the first place you will turn to. Its structure allows for it to deliver serious power to the battery when you need to.
Interestingly, it continues to grow more powerful as you use it so that it will perform well even after an intense task. This makes it a great option for heavier equipment, automobiles, stock cars, and diesel cars.
ACDelco 94RAGM battery
This is highly appealing both in weight and design. The battery is made of a calcium-silver alloy, and the vent cap will repel leaks and improve long-term performance.
Universal deep cycle battery
This is probably the best compromise for those wanting AGM batteries but without forking out as much as you would when buying an Optima. The only problem with it is the size – it is quite big, so you must ensure it fits in your car.
Odyssey LTV 65-PC1750T
Among the best AGM batteries for their battery performance, this ranks among them. The manufacturer behind the product even claims that the battery life supersedes other batteries by as much as 70%, with a relatively shorter charge time of 4 to 6 hours.
What we like
- These batteries are spill proof
- Durable and high-quality build
- Easy to mount
- Have a high power output
- Reliable use and safe
- Longer lifespan
What we do not like
- Can have issues with overcharging
- High cost of manufacturing
- Have issues with declining capacity as they age
What can you see with the AGM battery?
- Lower internal resistance compared to other batteries
- The fiberglass structure makes them spill proof
- Easy to recharge and use
- They perform very well in lower temperatures
Verdict: So, which is the winner? The deep cycle or the AGM battery?
Since these two are very similar, it can be difficult to say which is better than the other.
However, from a general use standpoint, it is a better option to go for the deep cycle battery, as it has many more applications and the ability to discharge deeply, which you might not always find with the AGM battery.
Remember, though, that your choice will depend on several factors, such as what you want to use the battery for and the purpose you want to accomplish.
What Is the Difference Between a Deep Cycle Battery and a Regular Battery?
A deep cycle vs regular battery difference lies in their functions. A deep cycle battery is designed for slow and continuous discharge over a long period, commonly used in applications like golf carts or solar power systems. On the other hand, a regular battery is better suited for short bursts of high energy like starting a car engine.
Frequently asked questions
What is the battery type I should use for an RV?
The answer to this, especially when comparing AGM and deep cycle ones, will lie in your power consumption, the space in your engine, and the battery you can afford.
The only thing to note is to avoid using regular batteries because of their short operation life and safety concerns since you will sometimes need to discharge the battery.
Can I use a deep-cycle battery to start an engine?
In theoretical terms, it is possible to do so. The only exception to this is when you use a deep-cycle marine battery; in that case, you are better off buying a dual-purpose model.
When I buy a car, why can’t I have an AGM or deep cycle battery supplied with it?
The reason behind this is the high production cost that AGM and deep cycle batteries, in general, have, which results in their price being more expensive than a regular battery.
