Best AGM Battery Chargers: Restore Your Vehicle Batteries
Save time and money with these efficient AGM battery chargers
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PUBLISHED ON October 29, 2019
Over time, vehicle batteries will lose their charge, especially if you don’t use them on a daily basis. However, if you find yourself with a low or dead battery, you don’t have to spend cash on a brand new one. An AGM battery charger can restore power back to your cells, so you can drive another day. If you want to save some money and keep your battery going, consider these AGM battery chargers.
- Best OverallNOCO Genius G3500 AGM Battery Charger and MaintainerSummarySummary
A powerful, rugged, and portable 10-amp AGM battery charger. It's designed to be used in the garage, house, or marina.ProsPros
It’s able to charge batteries quickly and efficiently, features a smart firewall to prevent fires or overcharging, and it’s waterproof.ConsCons
The screws holding it together aren’t the most durable, and it’s heavy and bulky.
- Best ValueBattery Tender 12 Volt Automatic Battery ChargerSummarySummary
Charges all maintenance-free 12-volt AGM and gel cell batteries. Four-step charging gives your battery optimized power without the danger of overcharging.ProsPros
Reverse polarity protection. It will not spark when you connect the leads. Twelve-foot output cord. Two-color LED charge indicator.ConsCons
Not waterproof as advertised. The unit may not last very long.
- Honorable MentionSchumacher Fully Automatic Battery Charger and Engine StarterSummarySummary
The unit has an automatic voltage detector and a digital display for alternator and battery testing. It also provides a 100-amp engine starting for trucks, SUVs, and large batteries.ProsPros
This charger has auto-voltage detection for 12- and 6-volt batteries. The digital display makes your readings easy to see. The charger is microprocessor-controlled and has float-mode monitoring.ConsCons
May overcharge the battery. The charge rate can be slow.
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Benefits of an AGM Battery Charger
- Battery longevity. Charging and then keeping your battery fully charged goes a long way toward making it last longer, especially under extreme hot and cold conditions.
- AGM specific. AGM battery chargers are designed, engineered, and manufactured specifically to address AGM battery characteristics. This gives you a charger that is tailored to your AGM battery’s requirements.
- Power when you need it. If you keep your battery in your motorboat, ATV, or motorcycle fully charged, the vehicle will be ready to go when you want to use it. There’s no need to wait for a recharge.
Types of AGM Battery Chargers
This type is in the middle of different types. This charger does not recharge a battery that is drained completely, but it also does not restore battery cells to their former healthy state. Using this battery charger will help a battery that still has some power in it from running out of power completely while providing some cell maintenance.
This battery charger is the type most buyers should consider. The industry considered it more or less a standard because it handles many battery types, and the most varied amperages and voltages. This charger is less expensive than more specialized versions.
As part of its function, this battery charger reconditions the battery so it can again take a charge. It does this by using some of its charging energy to realign battery cell elements and break down contaminants. A good type of battery charger for fleets and companies that have vehicles where the batteries frequently need restoring.
Joseph Henry Nook established this company in 1914 in Cleveland, Ohio. He was looking for a formula that would prevent battery corrosion. After hundreds of attempts, he found the correct one and the company took off. In addition to battery chargers, the company produces solar panels, jump starters, and portable power units. The main office remains in Cleveland. Research and development is in Phoenix, Ariz., with other branches in the Netherlands and Hong Kong. Check out the Genius 10 charger and the Boost Plus charger.
This family company began in 1965. Deltran Battery Tender continues to be located in Leland, Fla., where it designs, engineers, manufacturers, and distributes microprocessor-controlled products. In addition to battery chargers, these include batteries, jump starters, solar panels, inverters, and electronic accessories. Popular battery chargers include the Battery Tender Plus and the Weather Proof Battery Charger.
Schumacher Electric Corporation began operation in 1947. It is located in Mount Prospect, Ill., where in addition to battery chargers, it designs and manufactures batteries and battery testers, jump starters, and power converters, among other products. It is also active in NHRA racing. Schumacher products for the private vehicle owner and for professionals alike include the Rapid Battery Charger and Maintainer and the ProSeries Charger and Engine Starter.
Best AGM Battery Charger Pricing
- $20-$50. These are great chargers for charging 12-volt flooded, lead-acid, and sealed maintenance-free batteries, both gel cell and AGM. They often include an 80-hour safety timer.
- $50-$100. These chargers improve longevity and performance and will keep your vehicle batteries maintained and full-charged all year long. They’re also great for use on batteries in long-term storage.
- $100-$200. These chargers are USB-port compatible, which means they are a good fit for charging tablets, smartphones, and cameras.
Manufacturers place super-thin fiberglass mats between the plates inside the battery. The plates are infused with battery acid as much as 95 percent. The process packs the mats tightly between the plates and then lightly presses them. This produces a battery that is less prone to vibration, which allows the battery to last longer.
If the battery is constructed so there’s little vibration, it means it is less likely to break down, too. A battery that is unlikely to fall apart or explode is an obviously a safer battery.
There are a number of different battery designs in use in today’s vehicles. AGM battery chargers are made specifically to address AGM battery characteristics. If an AGM battery is not charged properly with the right equipment, it may discharge too fast and become unusable. If you charge an AGM improperly, it can also lead to overheating the cells and to the battery’s destruction.
- Type of charger. Research the type of AGM charger you need. There exists a vast difference between a charger that charges, for example, cell phone batteries or truck batteries compared to one the charges car batteries.
- Quality. Research and read the reviews to determine if the AGM charger you’re thinking of buying is made by a reputable company and works the way it’s supposed to.
- Price. There’s no sense in spending $100 when you can spend $49 and get a charger that’s going to do the job very well. On the other hand, you may want to spend a few more dollars to buy a better AGM battery charger than one that has a questionable operational record.
Best AGM Battery Charger Reviews & Recommendations 2020
Best Overall: NOCO Genius G3500 AGM Battery Charger and Maintainer
Use this AGM battery charger in the house or garage or at the marina. It charges and maintains a wide variety of vehicle batteries, such as in boats, cars, trucks, tractors, RVs, SUVs, and motorcycles. The charger features a repair mode to reverse damage to batteries that have been uncharged for a long time.
Made of durable, heavy-duty plastic, this charger is rugged. The leads have fray preventers at the base of the charger itself, on the leads, and on the power chord. It is waterproof, so you don’t have to be concerned about water damage at the marina and in other wet areas, and it’s portable so you can charge what you need, where you need to.
This AGM charger and maintainer features a firewall to prevent overcharging and fires, a reverse polarity safeguard, and a spark-proof design. Be careful: some users have reported the screws that hold the unit together aren’t the best. While the unit is portable and handy to use, some would prefer a charger that is less bulky and lighter.
Best Value: Battery Tender 12 Volt Automatic Battery Charger
This versatile charger has spark-proof lead connections, reverse polarity protection, and a 12-foot output cord. It’s great for charging 12-volt lead-acid batteries, maintenance-free batteries (both AGM and gel cell), and flooded batteries.
The recommended four-step charging program helps prevent overcharging and gives you optimum power. After the battery is fully charged, the charger automatically switches to float mode. A solid-state color LED indicator tells you the state of the charge; if the battery’s voltage dips excessively under load, full output begins again.
Be careful around moist conditions. The manufacturer indicates the charger is waterproof but some users state that it isn’t. Other buyers have reported the unit worked good for a time but stopped working way too soon and should have lasted longer.
Honorable Mention: Schumacher Fully Automatic Battery Charger and Engine Starter
This Honorable Mention AGM battery charger from Schumacher also offers 100 amp starting for trucks, SUVs, and large batteries. The charger automatically detects voltage on 12- or 6-volt batteries and has a digital display that is easy to read.
A microprocessor controls the unit, which makes readings accurate and reliable. The charger has automatic float-mode monitoring, so the battery is charged and maintained correctly. This charger also has reverse hook-up protection—an additional safeguard for your battery.
While many users report good results, some have reported the charger overcharged their battery. Others have stated that the charge rate is slow compared to some other chargers.
- Always clean the battery cables before you use or charge them. Debris and dirt can build up under the clamps and reduce the amount of energy transfer.
- If you spot a white powder on the battery terminals, it is dried sulfuric acid. The powder can burn your skin, so consider wearing gloves when handling the battery.
- Make sure you know which cable is the positive and which one is negative to properly charge your battery. A “plus” stands for positive while a “minus” stands for negative. Many are also color-coded to make things easier.
Q: What does AGM stand for?
A: AGM means absorbed glass mat, and it’s a specific type of lead-acid battery. It absorbs the sulfuric acid with a very fine fiberglass mat and makes the battery spill-proof. They typically have a much lower internal resistance and are capable of delivering high currents on demand.
Q: Will jump-starting a vehicle charge the battery?
A: Technically, yes, but it isn’t a full charge. You may be able to drive the vehicle until you turn it off again, but eventually, it may die again. Battery chargers are designed to charge the battery completely.
Q: How do I clean the battery terminals?
A: To properly clean away any sulfuric acid residue from the terminals, use a thick wire brush. Once the powder is wiped away, spray the terminals with an anti-corrosion spray to reduce the amount of acid that appears on them. Always wait until the spray is dry to connect the battery charger.
For a strong and successful charge to your battery, consider the NOCO Genius Gen1 AGM Battery Charger. For a versatile but less expensive option, consider the Battery Tender 12 Volt Automatic Battery Charger.