What is the Best Battery for Airsoft Guns?

Airsoft guns need a source of power to send the 6mm plastic projectiles flying towards their target.  So, if you have chosen an Automatic Electric Gun (AEG) Airsoft replica, you will need a battery to power your weapon (even a back-up or two, for out in the field).  With so many battery types available, you may wonder, “What is the best battery for Airsoft guns?”

As a whole, to get the most out of your Airsoft replica, Lithium Polymer (LiPO) batteries are the best choice. LiPO batteries offer higher capacity translating into a better Rate of fire and better trigger response. LiPO’s come in a variety of packaging and are light weight.

LiPO batteries have become the go-to option among many Airsoft players.  However, I would be remiss if I didn’t cover a little bit more battery information and the other battery types available.  Let’s take a moment to become familiar with some battery terminology that you may not know.

In this article we will discuss:

Battery Terminology

Here are a few terms that are commonly used in conjunction with Airsoft batteries.

Capacity: This refers to the amount of power a fully charged battery contains. Capacity is typically expressed in mAh (milliamp-hours). The measure of mAh is used to describe the energy that a battery will hold as well as how long the device will operate before needing to be recharged.  For example, a 1,000 mAh generally means you can expect to get 100 mA for about 10 hours usage, or 10 mA for 100 hours, or 1 mA for 1,000 hours.

Discharge “C” Rating: This is the measure of how fast a battery can be safely discharged without causing damage to the battery. This is often expressed as a continuous number of amps that can safely be discharged before the degradation of the battery or total battery failure occurs. Some simple math using the “C” rating and the conversion from mAh (divide the mAh by 1000) will give you how much can safely be discharged.  For example, a 25C, 1200 mAh battery can safely discharge a maximum sustained load of 30A.  (25 multiplied by 1.2)

Nominal Voltage: This refers to the average voltage a cell can output when charged. This is a resting voltage and not the full charge voltage reading of a cell.

QUICK TIP: Before juicing up your AEG, always follow your replica’s manual for the recommended battery type and rating.  Overpowering an Airsoft replica can result in premature wear of your replica’s gearbox and working mechanics. 

Lithium Polymer Batteries (LiPo)

Lithium Polymer (Lithium-ion Polymer) batteries have become very popular in the Airsoft world.  These light-weight power sources can yield higher voltages and current ratings. While this won’t make you an expert marksman on the field, it does provide benefits over traditional batteries.  LiPO batteries are more resilient to cold than other batteries. They take up less space and are lighter in weight. Also, due to their higher voltage and current capacity, a higher ROF (rate of fire) is possible.  If you decide that LiPO is the battery type you intend to use, care should be taken to properly upgrade your Airsoft gun in order to be able to handle this increased ROF.  The increase in ROF can cause greater stress and wear on critical weapon components resulting in premature failure of the replica weapon.  A single LiPo battery cell is 3.7v and battery packs are common in voltages of 7.4v (two cells) & 11.1v (three cells). LiPO’s require a LiPO compatible charger that can balance the charge.  This ensures an equal discharge rate.  When storing a LiPO always check that the LiPO doesn’t drop below 3.0v.  Discharging below 3.0v will almost always result in the battery not being able to accept a charge.

QUICK TIP: Do not fully discharge your LiPO batteries.  Once a LiPO battery is completely dead, it cannot be revived through charging. Also, if your LiPO battery should become inflated or “puffy”, it is no longer viable and should be safely disposed of.

Alternative Battery Options

While LiPO’s are currently what’s “in”, there are a couple of battery types that are still used in Airsoft guns. It’s not uncommon to find that most AEG’s will operate particularly well with batteries in the 7.4v to 9.6v range. However, not all batteries are created equal.  Each of the following battery types has its own chemical makeup and in turn, its own benefits (and deficits).

Alkaline

There really is not too much we can say about this type of battery as it relates to Airsoft.  Rarely do we see Alkaline batteries used in Airsoft guns unless perhaps you are plinking with a cheap toy.  Alkaline batteries can last for years on the shelf, are sourced easily and are relatively cheaper to buy.  However, they are primarily a single-use battery and not especially capable of handling the demands of today’s Airsoft replica weapons. We find it best to leave these type of batteries to accessories.

Nickel-Cadmium (Ni-Cd)

Nickel Cadmium batteries once ruled the hobby scene, primarily because they were pretty much the only rechargeable battery in their day.  Ni-Cd batteries are one of the older rechargeable battery types that have seen usage in Airsoft weapons.  Nowadays, Ni-Cd batteries are becoming less popular and less common in the Airsoft world.  Ni-Cd batteries recharge quickly, but produce a lot of heat during charging.  Ni-Cd batteries provide a decent rate of fire, but their mAh rating is pretty low.  One complaint among Airsoft players is that this type of battery can suffer from a “memory effect”.  This “memory” degrades over time if the battery is not properly maintained.  Ni-Cd batteries should be charged in accordance with the manufacturers recommended charging rate to avoid damage or possible explosion.  Ni-Cd battery cells are 1.2v each.

QUICK TIP: Ni-CD batteries should be fully discharged before recharging to preserve the lifespan of the battery and help lessen degradation or “memory effect”.

Nickel-Metal Hydride (NiMH)

Nickel-Metal Hydride batteries are better suited for Airsoft weapons than the older Ni-Cd type batteries.  Although they do not charge nearly as fast as Ni-Cd batteries, they are safer.  NiMH batteries are designed to maintain high voltage even during higher current demands.  They are less prone to suffer from the “memory effect” and can be topped off without fear of losing capacity.  NiMH batteries can operate better in colder environments than Ni-Cd batteries. NiMH battery cells are 1.2v each and batteries come in 8.4v & 9.6v.

Battery Shapes

As you now know, Airsoft battery types each have a different chemical makeup.  These chemicals are packed into cells that are arranged in a variety of shapes in order to create the desired voltage.  Battery cells are also arranged to accommodate the correct fit for a specific type of Airsoft replica. Each type of battery comes in a variety of shape and/or sizes.  Here are some common battery shapes:

The Brick

Typically, this is one of the larger battery shapes requiring more room to accommodate its size. The brick may also be referred to as a “Large” battery type.  In rifles, the “brick” is commonly found in a hollowed-out portion of the replica.  A hollow stock is a perfect example of this, as it allows more room to house the battery. Seven celled batteries are arranged in columns with the last cell capping off the bottom of the battery pack. Eight celled batteries have an even number of cells on each column of the battery.  Some examples of full stock guns that can accept this type of battery are the M16, MP5, and the full stock version of the AK-47.

Stick

Just as the name implies, the stick-shaped battery pack is a straight line of battery cells aligned end to end. Stick-shaped battery packs are commonly used in Airsoft AEG’s that have limited storage space.  Typically, the limited space is due to the replica not having a full stock.  Batteries of this type are most often found in Airsoft replicas with handguards and folding stocks. These are common amongst AK-47’s and their variants sporting a folding stock.

Nunchuck

You might have guessed that these batteries cells are shaped like a pair of martial arts nunchucks.  The battery cells are arranged in even columns which are joined together by wire.  Just like the stick-shaped battery pack, this battery pack is arranged for use in Airsoft AEG’s that have limited storage area.   Nunchucks are commonly housed in the forearm or crane stock of Airsoft rifles such as the M4 rifle.

Battery Connections

Just as you will need the correct battery shape and rating for your Airsoft replica, you will also need to have the correct connector in order to connect to the battery to the gun. The following are some really common connection types among Airsoft replicas.

Deans

Deans (also called “T Connectors”) are not the type of connector that is commonly found on stock Airsoft replicas. Deans connectors are more of an upgraded connection known for its small size and its ability to provide better contact.  Deans use a tab connection system as opposed to a bullet system.  The tabs on a Deans connector use spring tabs to maintain contact pressure.  This pressure results in better contact which in turn, translates into less circuit resistance.  Less resistance means better performance, and who doesn’t like that?  While they are the go-to connector, Deans connectors tend to have a sensitivity to heat.  So, be take care during soldering to avoid damaging the connector.  Also, be aware that knock-offs exist in the market place.  While some may be as good of quality, others have been regarded as complete garbage.  Buyer beware…

Tamiya

This is pretty much a stock connector.  The Tamiya connector is characterized by two pins housed in plastic.   The plastic separates and insulates one pin from the other making them safer in wet conditions.  One side of the connector features a round end and the other a square end. Just like the Deans connector, this odd shape help prevent the connector from having the polarity reversed.  Unlike Deans connectors, the Tamiya connector suffers from looser connectivity resulting in greater circuit resistance. Tamiya connectors also come in a smaller version, the Mini-Tamiya connector. The mini version is wired in reverse polarity.

The Battery Charger

Regardless of which type of battery you use in your Airsoft replica, you will need a way to recharge the battery when the power has been depleted.  If your Airsoft replica came with a battery and charger, then all you need to do is to read and follow the recommended procedures for charging the batteries from the owners manual. Not all batteries are alike and batteries will have different charging requirements. For example, LiPO batteries require a LiPO compatible charger.  Always refer to the documentation that was supplied with either with your battery or your Airsoft weapon (if the battery was supplied with your replica) to be sure that the charger is compatible with the battery.  This may require a little research, but improper charging will destroy a battery.  The worst case scenario is you will have a battery explode if improperly charged.  NEVER leave your charging battery unattended.  You don’t have to hover over it while it charges, but do not leave it charge in the house while you go to the grocery store.  It’s best to be close by so that you can handle any situation that arises quickly.

QUICK TIP: Get a good  smart charger. Smart chargers will safely charge your battery.  Some smart chargers can detect when the battery has been charged and cut-off charging when the battery is fully charged, helping to prevent overcharging.

Battery Disposal

So, what to do with your old batteries? Read on…

Lithium Polymer

LiPO batteries are landfill safe and can be chucked in the garbage once fully discharged.  It is safe to completely discharge them for disposal.  Once discharged, it is recommended to soak them in a salt water bath to ensure full discharge (salt water is conductive and will help discharge further). It’s been advised that soaking should continue for 24-48 hours.  Check the battery to ensure it is at zero volts.  Once at zero volts, it is ready to be disposed of.

Ni-Cd and NiMH

These type of batteries need to be properly disposed of and cannot be thrown  into the garbage with your household waste. These should be drained to zero volts and properly disposed of at a local disposal or recycling center. Also, some electronic or battery retailers with take batteries for disposal.

QUICK TIP: Some companies actually have replacement warranties you can take advantage of. Check to make sure that any warranties for your battery have expired before taking the disposal steps.   

Conclusion

LiPO’s will give you the advantage of being able to play longer with a better rate of fire due to their higher capacities.  For whatever reason you should decide that LiPO’s aren’t your cup of tea, there are other batteries available.  Keep in mind that any battery will need a compatible charger once the batteries have depleted their energy.  By properly charging and maintaining your batteries, you will enjoy many battles on the field.

See you out on the battlefield!