There are many reasons to choose the best AGM battery for a car instead of the lead-acid flooded or gel batteries. So what is an AGM battery? The abbreviation goes for “absorbed glass mat”. The place between the plate and wrappers is filled with the fiberglass that forms a peculiar cellular web. It holds the electrolyte inside by way of the capillary action.
The battery always holds its contents inside and is secured against any leakage. The electrolyte would not spill (as it would in the flooded lead-acid batteries) preserving the battery capacity and saving the nearby area from burning. The battery posts don’t get sulfated, while the battery and car parts don’t suffer from corrosion.
Such a dense structure provides for the steady operation of the absorbed glass mat car battery in any conditions and any position, too. It can be put on its side or even turned upside down, without any effect to its operation or capacity. It also ensures the minimal liquid evaporation that is frequent in flooded and even gel batteries in hot temperature. That’s what justifies it as the best AGM battery — it’s maintenance-free mode.
The innovative structure design of the best AGM car battery enables it to produce a higher voltage and in less time than gel or flooded batteries. It also gets recharged very quickly.
The Best AGM Batteries Reviews
In general, the AGM batteries for car don’t relate to deep-cycle batteries, while the best AGM marine battery would frequently be a deep-cycle battery.
The Best AGM Car Batteries
Odyssey 31-PC2150S — Long Life at Extreme Temperature
This high-end power bank for car has considerable CCA factor (1150) and is fully weather- and temperature-resistant. It can hold the charge and crank the motor equally well in the 113F heat and in 40F cold not suffering from rain or snow. It discharges slowly featuring the 70 times the cycle of the conventional lead-acid power banks.
The sealed enclosure and absorbed glass mat stuff ensure the high anti-leakage properties of the battery. It is sturdy and heavy, while not being large — the battery fits well even the tightest battery spaces.
This power bank could be called the best AGM deep cycle battery, as it can supply its full capacity without losing operational quality. However, the years of the confident usage cost quite high — the price for this battery exceeds most of the solid conventional models in times.
- A quick recharge from the bottom level to the full capacity within 6 hours.
- Steady voltage, zero-vibration, and impact shock protection ensure up to 400 recharging cycles at 80% drain.
- Slim yet quality handle for the comfortable carrying along and installment.
- Incorrect charging can result in decreasing the battery capacity.
- Might be an overkill option for small cars.
DieHard 38275 — Vibration-Free Sturdy AGM Car Battery
This solidly built standard AGM battery is a good choice for summer driving. It has a reliable intrusion-safe coating that isn’t easy to scrape. The sealed structure allows no liquid to come out even at considerable shaking and non-standard positioning. It also provides for battery’s vibration resistance, enabling its efficient usage in different circumstances.
This powerful battery has a special suspension system additionally preventing the electrolyte from spilling. It serves well the battery’s internal components and prolongs its life. The recharge is performed fast; 100 minutes are enough to get the fully loaded power bank.
For its reliability, this model could be called the best AGM car battery. However, it won’t maintain the same high rank among the winter-bound AGM battery reviews, as it has a low level of cold cranking amps.
- The battery provides steady current supply and instant cranking of the motor even after long idling period.
- The battery plates are full-frame ones securing the power bank from the short circuit.
- Flexible yet durable handle enabling the comfortable weight distribution while carrying.
- The battery is quite large and might not fit in a small-to-middle battery seat.
- Limited space around the battery posts enables only one way of the battery’s placement.
ACDelco 94RAGM — Enhanced Engineering Design for Longer Battery Life
This large AGM automotive battery has a standard cycle of operation, which is developed by its smart inner build. The battery has free quick acid circulation that ensures efficient cooling and disables any short circuit malfunction.
It has enough power to charge highly demanding motors of all-road cars, tractors, and other agricultural vehicles. It provides fast and safe cranking of the motor and optimal work of the car’s electronic system. It would deserve a title of the best AGM battery in the current AGM battery review, be it a deep-cycle battery. However, this power bank doesn’t “like” exhaustive drain and performs at its best until half of the battery charge is available.
The power bank has an original design of the vent cap that prevents the leakage and guarantees spill-free operation in different battery positions. The negative plate is solid and densely covered with the Silver Calcium alloy that improves the battery’s performance. The positive plate is made of Calcium Lead providing low resistance and enhanced circuit conductivity.
- Good charge keeping and steady operation in cold weather conditions.
- Two handles make it easier to install the battery.
- The battery is well-proportioned to fit most of the standard car battery compartments.
- Might be incompatible with older cars quickly losing its capacity.
- The battery is quite heavy.
Optima Batteries 8025-160 — Long Cycle and Large Reserve Capacity
This powerful 12V AGM battery makes a good solution for long driving trips. Even if the car’s alternator breaks, this battery has spare 90 minutes of the intensive work and will keep the electronics on within this time. It boasts long life and reliable performance at any level of the battery capacity. The charging is quick and non-demanding, though the best cranking power is emitted at the next-to-full capacity.
The battery is protected from external impact by enforced vibration resistance and sealed design. It ensures problem-free starting at rain or other unfavorable conditions. The cold weather amps make 720 CCA, which is enough for the majority of climate zones. Due to low internal resistance (0.003), the battery holds the charge well. Its nominated C20 capacity makes 44 Amp hours, while at the moderate use it can last even more.
- The enhanced anti-leakage design makes the battery performance sustainable.
- Plenty of space around the battery poles allows connecting it at various positions.
- The unusual design enables the battery to fit well even in the non-standard battery seats.
- A charge holding might decrease in quality if the battery gets drained.
- Can’t be charged with a trickle charger.
The Best AGM Marine Batteries
VMAX MR127 — Sustainable and Powerful
This power bank holds its top place in the marine deep cycle battery reviews due to its strong and long performance. It emits steady 12V able to power the high-demanding trolling motor within 100 Ampere-hours. Cobra, Minn Kota, Sevylor, and other motors can be connected and used within several hours.
The battery has a highly porous suspension mat that keeps the liquid within. It doesn’t spill even after the small damage. The inside stuff of the battery is made without any contaminants like silica gel or others. It has thick lead layers enhancing conductivity and ensuring good charge keeping.
The battery has cables supplied with it. Overall, this sturdy power bank could definitely be called the best AGM marine battery if the battery posts were easier to deal with – they are quite tough to screw and unscrew.
- Doesn’t lose capacity at the low charge level – can be drained several times without affecting the overall performance.
- Steady operation and optimal charge hold at both cyclic or floating mode of work.
- Built-in handles ease up the carrying and mounting of the battery.
- High price.
- The battery is very heavy, so it might not fit very light boats.
Optima Batteries 8006-006 — Steady Operation in Cold Weather
This power bank is a perfect choice for winter fishing or other boat travels, as it provides 800 cold cranking amps. It means any boat motor will start and work without issues even in extreme cold and can operate well upon complete discharge.
The battery is made of quality materials allowing it to hold the charge efficiently and have reserve capacity exceeding 1.5 hours. It keeps the electrolyte inside the glass mat, so the battery is spill-proof and highly vibration-resistant. It doesn’t let the acid goes through even if there are scratched or damaged. Thus it is highly safe.
This battery has a relatively small size, which allows it to be rated high in deep cycle marine battery reviews. However, with its open placement of the posts, it can also fit as the recreational vehicle power source.
- The battery posts are made of stainless steel ensuring rust- and sulfate-free clean surface and perfect conductivity.
- The battery capacity is enough to power the boat motor and electronics.
- Compact size provides for more space in the boat.
- Upon several full-load deep cycles, the battery discharges faster.
- Sensitive to the charger specs; the incompatible charger can break the battery immediately.
Vmaxtanks MR137 — Long-Lasting Charge for Various Types of Boats
This versatile battery holds its high rank in all the AGM deep cycle battery reviews. It can power up different motors including the Minn Kota, Sevylor, and Newport ones. It is designed for heavy-duty work with trolling motors and doesn’t require any maintenance during the whole battery life. The latter can reach even 10 years (provided the power bank works in the floating mode).
The battery has reliable strongly built grids covered with a thick alloy of lead-tin. This ensures perfect current conductivity and fast charging. The acid is kept in the porous structure of the absorbed glass mat and transferred to the battery posts immediately. The wreckage of the outer coating doesn’t result in any leakage.
This 12V power bank can run through several full cycles without any noticeable change in operation. It takes a little time to charge this battery.
- Considerable life span of 120Ah secures even the long boat trips.
- Quality solid cables are supplied with the battery.
- The battery weighs two times the regular power bank of its class and is difficult to reposition or carry along.
- The optimal battery performance requires a smart charger application of the relevant amperage and mode of charging.
Optima Batteries 8016-103 — Immediate Cranking Power
This deep cycle marine battery works steadily in the floating mode. However, it easily deals with any trolling motor providing 870 cranking marine amps. The cold weather is not an issue thanks to the heavy-duty corps and 750 cold cranking amps delivering constant 12V current to the motor.
The compact size and enhanced AGM engineering design make this power bank a universal marine battery. Thanks to its top-quality liquid-suspension system (called SpiralCell), it keeps electrolyte and gasses inside not letting out any leakage and thus, not contaminating the environment even in case of the major damage. The battery stores and conveys the current effectively enabling constant supply during 55 Ampere-hours. The reserve capacity takes two hours, which is a nice additional security to have at any type of boating activities. It also fits the boats with versatile electronics.
- Solid grids and high-density anti-spill design provide for the outer impact protection and zero vibration.
- Fits both as a permanent and occasional application battery without losing its capacity.
- Quick recharge of the flat battery within a few hours.
- The work at the constant considerable load leads to a decrease in battery capacity and faster discharge.
- The battery doesn’t have a handle to lift and carry it along.
AGM: Brief Description
The technology dates back to 1980s and first sealed lead acid power banks. The inside structure is made of the fiberglass absorbing the electrolyte. The plates can be put flat or cylindrically. This type of battery has an enhanced conductivity secured by the very low internal resistance. It doesn’t grow sulfation on plates and posts and is maintenance free. AGM batteries take charge fast and can be drained up to 80% of their capacity.
AGM vs Lead Acid — Which One to Choose?
The AGM is a type of the lead-acid battery. However, it differs from the conventional (or sealed) flooded lead acid type:
- Safety. Small risk of gas emitting or acid leakage.
- No maintenance. No sulfation or degrading as much as flooded batteries, no fiddling with adding water.
- Power. Better conductivity faster charging with the constant voltage.
- Shelf-life. Can be kept out of operation longer preserving the perfect conductivity.
- Bigger cycle. Deep-cycle batteries can be recharged several times.
How Long Do AGM Batteries Last?
The enhanced chemical structure of the AGM battery provides for its longer life cycle. They are supposed to serve without issues for three to five years. The heavy-duty models and the properly maintained ones can reach eight and even ten years of life. The battery-damaging factors are the following:
- Extreme weather conditions. AGM batteries work well in heat or cold, but the capacity can be deteriorated.
- Bottom-level discharge. Getting the battery flat will decrease its operational efficiency.
- Incorrect charging. Improper feeding leads to overcharging and kills the battery.
Are AGM Batteries Better than Gel Ones?
The AGM foresees a specific chemical structure filled with electrolyte. The Gel power banks preserve the electrolyte in silica gel cells. Both AGM and Gel batteries are spill-proof, vibration-resistant, have a low level of self-discharge, can be discharged up to 60% capacity preserving their capacity and charging properties. The difference lies in:
- Type of operation. The AGM ones are more efficient at cranking amps. The Gel can handle the floating charge better.
- Weather conditions. Gel batteries are less subject to extreme temperatures.
- Size. With the same capacity, the AGM batteries are smaller.
- Price. AGM banks are cheaper.