So what is a lithium polymer battery? Lithium polymer batteries belong in a class of batteries that uses a lithium base to create direct connection to power one way electrical systems. Basically lithium polymer batteries will provide power to your motor. So how is this different from nickle based or alkaline based batteries. Well the answer is in the amount of potential lithium based batteries can give systems. There is a reason why lithium batteries are used for laptops or in medical equipment. They are extremely reliable and extremely powerful for its size. They can be used in the cold weather better than nickle metal based batteries and they can give you great trigger responses. Since it provides more power and more punch, a lot of airsoft manufactures have capitalized on an idea called "lipo ready". They argue that you need a "better" gun in order to run lipo batteries.
Well I hope you do at least do some engineering KWA...
You want to know the reality of lipo ready? It's a marketing tool to lure in uneducated airsofters (like... literally... not meaning to insult anyone here). It was developed by KWA marketers (who hired a marketing firm down in California) to brand their rifles and to give it an additional perceived value boost. It also gives perceived quality ques about the product. It teases consumers into thinking that the gun is made better for specific use with lithium based batteries. Basically it is designed to show the consumer that this gun has incremental innovation. In reality its a myth. Its an idea created by marketers (like me) who are trying to increase sales.
I thought this was lipo ready...
When you think "lipo ready", you think 1) arcing and resistance and 2) gear train durability. In all reality most guns already have this. For 1, you technically don't need a mosfet (variable resistors, that may or may not be computerized) or low resistance wires to run lipos. The amount of wear a 7.4v 21 amp (1400 mah 15c) battery is less than a 9.6v 1600mah nimh (which runs at an equivalent of 8 C btw). The amount of amperage your motor technically needs is around an average of 30 amps meaning that feeding it more amps will decrease stress on the motor. Also most trigger contacts are using alloys resistant to arcing. Arcing is when there is a plasma discharge between connections that typically oxidizes the contact points. This oxidation causes impurities in the connection points which makes the connection less efficient. In worse case scenarios, it will prevent connection between the two points. Mosfets are thought to prevent arcing but in reality they wont prevent arcing, it will only decrease the amount of arcing caused by your gun. Mosfets puts additional stress on the gun by adding resistance to your electrical system (however I still recommend it for an 11.1 since it technically does help with arcing). It comes down to the end user to decide if a mosfet is for them. Doing a proper cost benefit analysis will go a long ways.
Example of a computerized mosfet
The second issue is gear train durability. Angle of engagement (AoE) and shimming is a HUGE must but most companies are already correcting AoE and already shimming their guns as part of their initial design. It really comes down to the materials being used. Is your piston a low density polycarb...? Then switch it out! However most polycarbs (and most materials used in the gear train for that matter) is already strong enough to handle lipos.
Even the best fails if it doesn't have the right support (Siegetek Gear strip)
Now realize it's not the lipos itself that cause issues. Problems are caused the by-products of lipos (and all lithium based products). Because of the increase amperage to your battery, you will see your motor running faster because its pulling the amps it needs to actually run efficiently. This causes your internals to move faster which means that you will reach your product degression rate faster. You aren't really putting additional wear on it, you are running it more efficiently. Each gear has only a certain amount of cycles before it dies and each spring can only retract so many times. By running it faster, you are just reaching these predetermined numbers earlier.
Also one more thing, your motor will only pull what it needs. Just because you plug in a 22.2v 100 amp battery doesn't mean it will pull all 100 amps. It will only pull 30 amps if it needs 30 amps. WOAH hold on. what is this random voltage, amperage bull crap? Well lets go over all that! Lets take a 7.4v 1400mah battery with 15-25c.
7.4v: This refers to the voltage of the entire pack. Since each cell holds 3.7v, this pack must have 2 cells wired in series. The common pack voltages you’ll see for airsoft use will be 7.4v and 11.1v, however, we are starting to see people screwing around with 22.2 and 44.4 battery backs to stress test their guns.
1400mAh: This is the capacity of the battery in milliamp-hours. Although not exactly, mah can be see as how long your battery will last. The larger the capacity, the longer the battery will last.
15-25C: This is the c-rating. The c rating is the discharge rate of the battery pack. This is how much the battery pack will discharge at one time. The first number normally denotes the constant c-rating. The constant c-rating is how much your battery will typically discharge. The second number normally tells us our burst c-rating. This is the absolute maximum your battery can discharge at one time. This normally happens during amperage spikes or if the motor pulls more than needed.
So how did I get those amperage numbers earlier? Here! I will show you that as well! The equation is pretty dang simple:
(C Rate x Capacity)/1000 = Discharge Rate (in Amps)
We can use the battery above as our example. Our constant c rating is 15 and our capacity is 1400. So if we take 15 and multiply 1400, we get 21,000 then we divide by 1000 and that gives us 21 amps. Pretty easy stuff!
In all reality, lithium based batteries are as common as nickle metal based batteries. They have more electrical potential and will make your gun function faster, better, and more efficiency. There is nothing to fear about lithium batteries. Most suspicion towards lithium based batteries are from older subpar (B and C level lithium cells) that were prone to catastrophic failure. Realize that most modern A level lithium batteries are top notch and actually take a lot to make them explode. My father, an electrical engineer, struggled to set one off with a hatchet and matches. We actually had to start a lead explosion in order to set it off. Saying that, there is some important facts that you need to know about them. 1) if your rounds per second (RPS) decreases, you need to disengage and change out your batteries. Lithium batteries have a very stable energy output (in comparison to your nickle metal batteries). When you shoot a nickle metal battery, you will notice that your battery will slowly decrease RPS over time. This will eventually lead to your gun not shooting anymore. A lithium battery will continue to show the same amount of RPS over time but then suddenly decrease is the charge reaches below 3.5v per cell. At 3.5v, your cell will only have around 4-5 percent remaining. In order to prevent damage to your lipo cell, you will need to change it out and charge it.
Well then... this escalated quickly.
Another thing you will need to understand about lipos is how interlinked each cell is to each other... but wait... what is this "cell"? A lipo cell is a cell that provides 3.7v. Each cell connected to provide a total voltage. These voltages compound on top of each other. If you have 2 lipo cells, you have 7.4v and if you have 3 lipo cells, you will have 11.1v. Easy enough! Its super important that these cells are charge and kept at similar voltages. Uneven voltages is an indicator that your battery is not good to go anymore. In order to charge these cells simultaneously, you are recommended to use a balancer. Even though you don't have you, realize that most if not all lipo users use balancers. Its a huge risk to charge otherwise. Most chargers will attempt to charge one cell at a time without a balancer.
One last thing I feel is important to note. There is NO difference between RC lipos and airsoft lipos. They are exactly the same compound and just come marketed to different target markets. Airsoft lipos do have the advantage of normally fitting buffer tubes and handguards (or where ever you wish to store your battery) but RC lipos tend to be cheaper. Just do some serious shopping before investing in "airsoft lipos".
Looks like this guy didn't read my blog about lipos... escalated quickly.
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