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Can I Replace EFB Battery to AGM Battery?

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EFB battery is a further development of conventional lead-acid batteries. The Polyvlies material on the surface of the positive plate guarantees that the EFB has a longer service life. EFB batteries have a low internal resistance and are characterized by twice the number of charging cycles* in comparison with conventional starter batteries, as well as a high load capacity.

EFB batteries are suitable for the power supply of cars:

  • with simple automatic start-stop systems
  • without start-stop, but with demanding driving requirements (e.g. in urban traffic),
  • without start-stop, but with extensive equipment.

With the expansion of the Start-Stop engines, almost every vehicle rolling of the production line will either require an EFB or the higher performance AGM type battery.

Many wonder if they can trade these batteries for more affordable EFB batteries. Knowing the differences between these two types of batteries will help you choose which is best suited for your vehicle.

Keep reading so you can make the right decision for powering your car.

AGM Batteries Explained

AGM batteries are a type of deep-cycle battery. They are sealed and maintenance-free.

The biggest difference between AGM batteries and other types of deep cycle batteries is that they use Absorbed Glass Mat (AGM) technology. You can consider this a sophisticated gel battery design that results in less electrolyte loss than more traditional flooded lead-acid designs.

Their sealed design improves the overall efficiency of your AGM battery. This results in a longer life span when compared to other types of batteries.

Charging AGM Batteries

AGM batteries are charged with a slow, constant current. You can charge them using a battery charger that has the AGM mode enabled.

The charger will power up until it reaches about 14.6 volts, or whatever energy level that the manufacturer considers appropriate. Then, the charging device will maintain this level.

This type of low-current charging is critical to the AGM battery’s operation. You can damage AGM batteries by overcharging or discharging too much.

AGM Battery Uses

AGM batteries are best suited for motorcycles, boats, cars, and RVs. In these applications, you can use AGM batteries in place of conventional lead-acid batteries. They will give you performance that is equal to or better than the conventional battery.

You can also use AGM batteries in off-the-grid power systems, such as solar panels. They’re useful for providing battery backup when there is no available grid power.

AGMs are ideal for anyone who needs more starting current from their vehicle than an EFB battery can provide.

27M-800 deep cycle marine battery
27M-800 deep cycle marine battery

Pros of AGM Batteries

These batteries will last a long time. AGM batteries can last up to twice as long as conventional batteries in deep discharge cycles.

They’re also spill-proof and vibration resistant.

Because of their construction, AGM batteries can’t leak acid. It doesn’t matter if you leave them on their side or upside down for days at a time. Because of this, these batteries are great for off-road vehicles that are prone to rolling over during use.

They’re less susceptible to damage caused by extreme temperatures. An AGM battery won’t freeze in cold conditions like those found in Alaska or Canada. It also won’t explode when exposed to heat from sitting too close to your engine compartment.

EFB Batteries 101

Enhanced Flooded Batteries (EFB) are a more advanced version of standard wet-flooded technology. They’re entry-level batteries that use the same chemistry as gel batteries, but in an innovative way that allows them to be used in stop-start vehicles. These vehicles require rapid charging and discharging cycles; something that traditional flooded lead-acid batteries can’t handle well.

Charging EFB Batteries

If you’re charging your EFB battery at home, the best way to do this is with a charger designed for EFB batteries. These chargers are able to charge your battery at higher voltages than typical car chargers and will help keep your battery healthy.

EFB Battery
EFB Battery

Pros of EFB Batteries

EFB batteries have several advantages over AGM batteries. The most significant advantage is their longer cycle life. An EFB battery can withstand more cycles of charge and discharge than an AGM before it reaches the end of its useful life.

Another advantage is that EFBs can be discharged to a greater extent than AGMs in high-vibration applications. This makes them better suited for vehicles like motorcycles, where they’ll experience a lot of shaking while in operation.

Even in low-voltage situations, EFBs have a much shorter recharge time than AGMs. Because they’re capable of accepting large amounts of energy at once without damage, recharging an EFB takes less time than it would if you were using an AGM battery.

Cons of EFB Batteries

EFB batteries are more prone to sulfation than AGM batteries. Sulfation is when the positive and negative plates of a battery get covered with an insulating layer of sulfur. This prevents the battery from being able to use its full capacity.

Sulfation occurs when you don’t charge EFB batteries to their full strength regularly. This leads to a significant decrease in performance.

EFB vs AGM Batteries

If you’ve got an entry-level start-stop car, EFB batteries might be the right choice for you. However, if your car has a higher electricity demand (such as those with larger engines), an AGM battery is probably better suited to your needs. Also, if you use your car for longer drives and constantly drain the battery, AGM batteries are a better choice.

Frequent drivers should consider AGM batteries because they’re more resilient to being drained and can withstand multiple charge cycles without losing their effectiveness. These types of batteries have superior temperature resistance and lower internal resistance, which means they’ll last longer overall!

EFB batteries are for entry-level start-stop cars

EFB batteries are a step up from conventional lead-acid batteries.

With up to two times longer cycle life than standard batteries, high load capacity and low internal resistance, BRAVA EFB batteries are ideal for use in start-stop vehicles without regenerative braking technology.

An EFB battery may also be a viable option if your vehicle doesn’t have start-stop technology but has demanding driving requirements or extensive equipment.

For more information, visit the dedicated EFB technology page.

Start-stop vehicles with high electrical demands require an AGM battery

Delkor® AGM batteries are the premium choice for high-end and advanced fuel-efficient vehicles with regenerative braking. An AGM battery has the greatest power reserves for supporting the electrical demands of start-stop vehicles.

If your vehicle was originally fitted with an AGM battery, it can only be replaced with another AGM battery.

See the AGM advanced technology page to find out more.

27M-580 Dual purpose battery
27M-580 Dual purpose battery

Can drivers upgrade from an EFB to an AGM battery?

Car batteries should be replaced with equivalent battery technology. But in some cases it’s worthwhile to upgrade from an EFB to an AGM battery, such as:

  • If you’ve added extra equipment, features and appliances that put more electrical demand on your battery;
  • If you usually drive short distances in urban traffic and your battery is unable to recharge sufficiently;
  • If your battery is only used seasonally and needs to be easily recharged.

Determining which battery is suitable for your car doesn’t need to be a headache. When you notice it could be time for a battery replacement, weighing up a few important points can help you make a more confident decision.

When Should I Upgrade from an EFB Battery to an AGM?

One important factor to consider when choosing a replacement battery for your vehicle is the cost of the battery itself. While AGM batteries are the best performers, they also come with the highest upfront cost. However, due to their longer warranties, high performance and above all else their longer service life, an AGM battery will typically be the most economical option in the long run. An EFB battery will come with a cheaper upfront price but may end up costing you more in the long run due to its shorter service life and inferior reliability when compared to an AGM battery.

If you have added any extra features, equipment or appliances to your vehicle which add a greater level of demand to your car battery, we would advise you to consider upgrading to an AGM battery. Similarly, if you usually drive short distances in which your battery is unable to sufficiently recharge such as in an urban environment or your battery is only used seasonally and needs to be recharged, we recommend that you fit an AGM battery to your vehicle for the best results.

Get Reliable Batteries for Your Vehicle

EFB and AGM batteries are a great choice for many drivers. If you’re looking for a high-quality battery that will last for years, then either option might be right for you. However, if you want something that can handle extreme temperatures and other adverse conditions, an AGM battery may be better suited to your needs.

You can speak to a professional at BravaBattery about which type of battery is right for your vehicle. Contact us today and one of our experts will help you make the best choice for your car.




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