|June 27th, 2006, 20:26||#1|
Battery FAQ *Now with more Lithium in it!*
I recently searched thru the forums infos on batteries... just to see what is the general knowledge of the community, and geez....
Most of you get a note of 3/10.....
First, a bit of terminology
This term stands for the amount of energy a battery can produce in Amps, during one hour. This also means that if you discharge a 600mAh pack at 1200mA, the pack would most likely last half an hour. The nominal capacity of a pack is usually refered as 1C. For a 600mAh pack, 1C = 600mAh. 3c = 1800mAh and so on. The opposite is also right. If you charge a 1200mAh pack at 2.4A, this means that the pack would be full in about 30 minutes. It also means that the higher this number is, the longer your pack will last. It CANNOT damage your gun if you use extreme high capacity packs. Current is not forced into a gun, the motor only takes what it needs.
The discharge rate is also using "C" as a mesurement unit. This means that a 8.4v 1200mAh mini pack, rated at 10C (most are 10C) can be drained up to 12000mA or 12A.
This is the unit used to represent the force of a pack or potential. The higher the voltage, the harder the battery want to push electric current out of the pack. It also means that the higher the voltage, the faster your gun's motor will spin, and the higher ROF you will get. Be carefull, as the faster you shot, the harder it is on your gearbox. The internal wires of you motor can also only take som much before it starts to heat-up and melt the insulation around it. It this happens, you motor will get very hot and have a hard time moving your piston. One a motor get's damages, it is not easy to fix. Easiest it to just change it for new one.
Amp (A) or milliAmp (mA)
This is the unit used to reprensent the current. It is the amount of energy in form of electricity that goes thru any electric device. Depending on the type of cell (AA, A, 2/3A, Sub-C) The amount of current that can go tru the pack is different. It is not good to have a pack discharged above it's rate. The pack will get hot quickly, and will eventually wear-out.
AA cells are about 2-3C (2-3 times the capacity of the pack)
A and 2/3A are about 10-15C
Sub-C can be from 20 to 35-40C (the newest packs are 45C, and are expensive, so if you bought your pack 15$, it mostlikely will be 20-25C)
Li-Po pack varie greatly. From 10C to 40C and even 50C (under 20C is no good for airsoft, so a pack under 1500mAh 15C can't be used in your gun unless it is under 300 fps.)
Peak or Delta peak or Fuzzy Logic or anything like that
This is the method used to detect the end of a charging cycle in Ni-Mh and Ni-Cd chemestry. It mesures the voltage of the charging pack. A typical curve will start rising fast, to gradually slow down and finally start to drop. The charger will detect a drop ranging from 5mv for Ni-Mh to 10mv fo Ni-Cd. It will then terminate the charging process.
This is the method used to charge Lithium packs. It first forces constant current in the pack until the voltage rise up to the "normal" level (7.4v for a 2 cells pack or 11.1v for a 3 cells pack). The charger will then only apply constant voltage to the pack and let it take whatever current it needs. The charge will finish when almost no current is drained into the pack.
This is the name for a single battery. A 8.4v pack is made out of 7 cells, 1.2v each. 7x1.2v = 8.4v
For Li-Po packs, cells are 3.7v each. So a 7.4v pack is made out of 2 cells, and 11.1v is 3 cells.
Type of cell
This is NOT the chemestry. It is the shape of the cell. (AA, 4/5A, 2/3A, Sub-C, etc.)
Li-Po cells are always rectangular. Their dimensions always change depending on capacity. They usually are long and wide, but very thin.
This is the kind of chemicals used in the fabrication of the cell. (Ni-Cd or Ni-Mh or Li-Po)
Ni-Mh : Nickel-Metal hydride
Ni-Cd : Nickel-Cadmium
Li-Po : Lithium-Polymere (full name is Lithium-ion Polymere)
General battery maintenance.
These actions are good to be followed for both Ni-Mh and Ni-Cd cells.
Li-Po packs have specific maintenance, so please refer to the right section of this post.
-NEVER short a battery pack! This is the best way to have it explode.
-Never charge a pack above the "safe" charging current for it's type.
-Cycling is good for your battery, if not abused. Ni-Cd or Ni-Mh benefit from a cycle discharge, but you ust be carefull as they are not to be discharged the same way, nor at the same frequency.
-Never charge a battery with a charger not designed for it's chemestry, or charging at the wrong voltage. A 8.4v charger is driving around 9.8v, just like a 9.6v is around 11v. Doing it will reduce the life of your pack by a lot, but the pack can also explode, causing damage to surrounding areas.
-It is normal for a pack to become hot. To know if a pack is too hot when charging or discharging (in the gun or on a discharger), simply have it on the inside of your forearm. If you can hold it there for 10 seconds, then it is alright. Some of you already know it, battery work better when hot but not TOO hot. Ask those who got a juice shortage in a winter game....
Ni-Cd vs Ni-Mh
This is based on both really experience and theory. Give or take, I don't really care. Just don't start arguing as this is not the point of this post. I am writing this to help those that need it.
In most cases a Ni-Mh pack will outclass a Ni-Cd pack by a lot. In some extreme cold conditions, It may seem that Ni-Cd packs are working better. This is due to the difference in chemistry. Try to wrap you Ni-Mh pack in some wool...(No joke) If you can keep the temperature of the pack above -10░c, it will still outperfom any Ni-Cd pack.
*Li-Po pack are fragile. Handle with care, and never let the pack get hit directly. One good thing to do is to wrap the pack in some foam before have it in the gun.*
*NEVER tape your pack directly, as it could tear the aluminium sleeve when removed.*
Lithium-ion polymere is one of the newest chemestry for batterie. These packs are about twice smaller and lighter than any Ni-Mh pack for the same capacity and can allow a lot more current to flow (Discharge rate). Some packs are rated 10C, and higher grade pack can go up to 30-35C (for a 4000mAh pack, this means the pack can kick 140A out to the motor. Again, the motor will only take what it needs.)
Li-Po packs are charged using a different technique than Ni-CD or Ni-Mh packs. It is called CC-CV, versus delta peak or peak charge. Never plug a Li-Po pack on a Ni-Mh charger. It WILL cause the pack to explode. Li-Po packs take about an hour to charge when empty. NEVER try to charge a Li-Po pack at a higher rate than 1C. For example, a 2000mAh pack must not be charged above 2A. These packs greatly outperform any Ni-Cd or Ni-Mh pack, but must be taken care in a different way.
It is a good thing to place a voltage cut-off between your gun and your Li-Po pack. Li-Po's must not be discharged bellow 3.0v per cell. They will start to deteriorate, and might eventually explode. A little voltage cut-off can be bought for about 10$, an will stop the pack from being overdischarged. If you don't want to use a cut-off, you will need to stop using your gun as soon as ROF start to decrease. This means that voltage is getting low. When your pack looks like it is inflated, it means that it was overdischarged.
Li-Po pack must NEVER GET HOT! If they start to heat-up, this means that the rating is too low for your usage (Drain rate), your pack is empty, it is charged incorrectly or it's life spawn is done. If your pack gets hot, unplug-it right away! Place it in a safe place, where it could not damage anything if it explodes, preferably outside. In normal conditions, the pack will not get hot. If missused, Li-Po pack can explode and cause great damage to material and people. Remember that Lithium is flamable in contact of water, so the humidity in the air makes it burst in fire. The packs are sealed in an aluminium sleeve, so the pack must be broken to explode. If your pack is inflated, this means it as been overdischarged. Dispose of the pack and don't try to use it again.
If you already had your pack heated, check for some gaz bubbles in the pack. These are easy to detect, it will seem as the aluminium sleeve it not attached to the internals anymore. Get rid of the pack as soon as you can. Recharging the pack or using it again can make it explode.
The Ni-Cad chemestry is one of the first efficient way to recharge batteries found. It allows the battery to reach a 60-70% efficiency when charging. This means that in theory, to charge a 2000mAh pack in one hour, we would need to charge it at 3000mAh. It is theory and might not be the best thing to do, depending on the type of cell.
It is good to discharge this type of cell every 2-3 charge. You SHOULD NOT discharge it EVERYTIME you charge it, as it will only shorten it's life. It will not develop the memory problem in a short period of time. This problem can apear after 10-15 consecutives charges without any discharge. It will seem that the pack is of lesser capacity than it should. IT IS NOT ABSOLUTE AND CAN BE REVERSED. You just need to deep cycle it using a good charger.
Even if it is good to discharge a pack, you should never discharge it bellow .09v per cell. Even if it is Ni-Cd, doing so can reverse the voltage of the cell and THIS IS IRREVERSIBLE, as the battery chemicals start to consume themself to keep producing energy.
Discharge current should ALWAYS be bellow 3 times the capacity of the cell. Higher rates can cause damage to the pack because the discharger will detect the low voltage condition too late. A 3000mAh pack should NEVER be discharged above 9A. See the table bellow for best charging/discharging rates for each type of cell.
When you want to store you Ni-Cd pack, you should discharge it first. This will prevent damage to the pack. Don't ask me why, I don't know. I just know that a pack stored fully charged for a whole year will decrease in capacity of about 30%. This is based on my own experiences AND battery fabricant's recommendations.
Ni-Mh chemestry is a recent technology developpement that improve a lot over the older Ni-Mh chemestry cells. It can hold a lot more energy in the same space compared to Ni-Cd. The charging efficiency also has been improved. It vary between 70-85%. Even if the chemestry is not the same, Each cell is still 1.2v, but both the charging and discharging method differ. Again, the type of cell (shape) is the most important factor in determinating the charging current.
The Ni-Mh chemestry allow to charge the battery even when it is not fully discharged. The so called "memory effect" does not exist in these cells. It still is good to cycle the pack in a few conditions. The first one is after you have not used the pack for a while. This is called a "wake-up" cycling. It must be a soft cycle, charging the pack around half of it's capacity and discharging near the capacity (1C).
The other case when it is good to discharge a Ni-Mh pack is after 15-20 charges. The chemicals inside the pack usually want to crystalise. The problem is that bigger the cystals, longer it is to have it react to create energy. It will not decrease capacity. In field condition, you might start to find your gun slow to react, just like when the pack is about to die. This cycling can be done at higher rates, fast charging the pack and fast discharging it. You still must keep the discharging current bellow 3 times the capacity of the pack (3C).
Just like Ni-Cd cells, Ni-Mh cells should not be discharged bellow 0.9v per cell. It is more important for Ni-Mh chemestry as they are slightly more instable, so they will change polarity more easilly (reverse voltage). Just like for Ni-Cd, this is DEFINITIVE.
An other difference between both chemestry is that Ni-Mh pack must be stored partially charged. You must first charge the pack full, then discharge it about 1/4th of it. The reason for that is that batteries will leak energy inside themself, there is nothing we can do about it. The only problem with this is that if the pack is fully discharged, the chemicals will consume themself to cover this energy demand, and will damage the pack in long term.
This mostly is what you must know to get better performances with your battery packs. It is basic knowledge, but still if you don't know...
After a few years, batteries have evolved a little more. Some china manufacturer start marketing "new" types of batteries for airsoft. Not all of them are good.
First is the recent trend to use Li-Po batteries in any and all guns.
I have personally used Li-Po for a few years now in most of my guns. NOT all my guns.
Since Li-Po packs are only avalaible in 3.7v/cell, this only allows us to use 7.4v and 11.1v packs for our airsoft needs.
Here is the trick:
A good (1500mAh or above, 20C) Li-Po pack of 7.4v will perform better than a 2/3A 8.4v (the standard "mini" pack).
This is because of the drain rate. In this exemple, the LiPo pack can deliver up to 20 times 1.5A. This means that the current that can flow thru the motor is around 30A. The size equivalent Ni-Mh pack (8.4v 1400mAh) is rated only 15C (that is for VERY good quality packs). This means that it can only deliver up to 21A to the motor.
This difference will be visible when the motor starts. Basically, the larger the current flow to the motor, the easier it is to turn it. This makes a difference since the motor will reach it's running speed faster that with the Ni-Mh pack. Even if the voltage of the Ni-Mh pack is higher, since the motor struggle to spin because of the reduced current, it will reach the same speed at a later time. This result in a slugish response in semi-auto and first 3-4 rounds in full auto.
If you have or plan on upgrading your gun above 350fps, the 7.4v pack will have a hard time racking the piston, just like the 8.4v.
This is where the larger 11.1v packs come into play. A 3cells Li-Po pack will have a fully charged voltage around 13v. That is a LOT. But for those running a 400-450fps rifle for summer games, it is the perfect battery.
The reason why it is not a good idea to use a 11.1v in a "stock" or sub-350fps gun is simple: the motor accelerate so fast that the gun will fire 2-3 times even in semi-auto. The gears have some innertia since they are metal, same for the motor's rotor. When using a weak spring, this means that the energy stored in the spinning gears is enought to rack the piston and spring two or three times AFTER the trigger is released.
When at or above 350fps, the spring is stiff enought to break the movement of the gears fast enought to prevent double/triple fire.
The second thing that has to be considered, is that the higher the voltage, the more heat the wires will have to support and the more chance there is that the trigger contacts arc.
So when you upgrade a gun for Li-Po use, it is a good thing to change all the wires for at least 16ga. It might be hard to fit in a V2 mechbox, but it is possible (I did it a few times already).
The trigger unit can also be changed for a "heavy-duty" or similar upgraded unit. Usually, the copper contacts are made thicker, meaning they can take more heat/abuse before getting damaged.
You can also use a high power transistor or MOSFET to re-route the current from the contacts. It effectively boosts the trigger response and completely remove any wear on the contacts. Response is enhanced since the motor-battery circuitry will have a very low resistance compared to the trigger-mosfet circuitry. This means more current will flow with less heat/energy dissipation.
Now if you want to keep it simple, don't use Li-Po. It is the same as when upgrading a gun above 450fps. A lot more parts have to be changed in order to have an efficient and reliable system.
The perfect example would be a 330fps CQB gun. It is too low to use 11.1v, but the ROF would benefit from an incread over the 7.4v/8.4v pack. Best thing to do it to use a 9.6v Ni-Mh pack. It will releive some strain from the mechbox and still give a decent ROF.
The second trend I have found is the use of "Li-ion" packs in stick configuration.
This might seem attractive since you can now fit a larger/higher voltage pack in the space of a stick pack. Great! A Lithium solution for these AKs and MP5s.
Not so much. They are not Li-Po packs, they are Li-ion. Same as these watch batteries.
I find a lot of these "Firefox 11.1v Lithium battery pack for AK stick" on eBay and other online outlets.
It is a shame that they do not actually give the right informations to customers.
Basically, would you rather run your gun with a flashlight battery of a regular battery?
Li-ion are moslty known as CR123A. They are low current, low capacity batteries that are used in high powered flashlights. CR123A is only one of the shape avalaible (just like AA, 2/3A and Sub-C for Ni-CD and Ni-Mh).
The other little hick, they are NOT 3.7v/cell. Only 3.0v. This means that they are avalaible only in 6v, 9v, and 12v configurations. The "Firefox" ones are then 12v instead of 11.1v.
Also, Li-ion have an energy density very similar to Ni-Mh. This means that is the pack takes the same space as a 1400mAh 8.4v pack, but it is 12v, the actual capacity is somewhere around 900-1000mAh.
Lastly, these are designed to be low-drain cells. They are made to be used for a long period of time, with little current flowing. Best Li-ions that could fit in the space of a 2/3A cell would have only a 10C rating. Not that bad since it is about the same as regular Ni-Mh. Think again. 10 x 1000mAh = 10A. When for Ni-Mh, 10 x 1400mAh = 14A.
The same way a 7.4v pack is better than 8.4v because of the drain rate, a regular 1400mAh 9.6v would outclass a 12v Li-ion pack for AK. Don't be fooled by the "Lithium", these particular packs are not good at all for the use they are intended.
They also require a special charger, not the same as Li-Po packs and not the same as Ni-Cd/Ni-MH packs.
All the AR fans out there must have been looking for a decent solution to using 11.1v LiPo packs with at collapsible stock.
Enter the 11.1v 1200mAh 12C Li-Po, in buffer-tube size!
I had the chance to try theses first hand in two occasions. I must say, these are not that bad for a few uses.
Every one knows that it is very hard to find a decent battery solution for any AR if not using a full stock or extenal PEQ box. Recently, there has been a lot of these "Firefox" buffer tube packs.
They are Li-Po and 11.1v, 10C or 12C. They fit in most buffer tubes for ARs and they can be found in 3-packs configuration to fit in the handguard.
Now, I had ARs before. A small 9.6v 1400mAh is barely enought for a 400 fps summer gun. And you better have a few spares in case.
The nice thing about these Li-Po is that they can actually fit inside of the "wasted" space of the buffer tube. They also are higher voltage than regular 9.6v packs that can be fitted in the handguard.
They are a tad bit to long to fit in the buffer tube completely. This means that you either have to modify your buffer tube or use a stock that covers the end of it (like a crane or vltor stock).
They are also very low rating (only 10-12C) and they are quite expensive. For the same price as one of these, I can get a 2000mAh 11.1v 20C that fits in the space of a 9.6v mini.
A decent use I found for it was for a 400 fps rifle that was built for my friend. He wanted to use a Magpull CRT stock with a RIS unit and no external battery boxes.
The battery was about 3/4" too long for the stock to collapse completely. We managed to fix this by installing a QD sling point on the buffer tube itself to prevent the stock from accidentaly being closed too much.
Since the battery acces was easy (simply slide the stock off) it didn't really mather that the pack lasted only a few thousands of shot (around 2000). He had 2 packs for day long games.
But since the pack is 11.1v, this means that it is not a good solution for sub-350fps guns. And the wires have to be modified.
I find the discharge rate to be a bit too low for high powered guns however. I never use anything under 20C for airsoft guns. Think about having a pipe bomb right next to you face if for some reason the pack gets over discharged...
It really is a case-by-case thing here. I you are uncertain about Li-Po, this is NOT the right place to start. A crane stock with a good 9.6v 3800mAh+ pack is easier to use and requires less maintenance. It is heavier though.
Finally. Chargers. What is good and what is crap.
There is a whole lot of chargers on the market, and most of the time this is the part that players skip over, too fast or too cheap.
I will just have a little guide line here as well as some no-go brands/models
This is one of the important part in your airsoft gear, yet everyone I talk to couldn't care less about it.
Most people ask me why I have a 300$ setup just to charge batteries. Believe-it, it is worth the price.
If you plan on using Li-Po packs now or in the future, you want to have a VERY good charger. If you don't want to spent a lot, buy a decent Ni-Mh/Ni-Cd charger and get a Li-Po dedicated charger later.
For Ni-Mh and Ni-Cd, the hot points:
You HAVE to be able to select the charging current. Not only two settings, a decent charger will let you set the current to anything between 500mA to 5000mA.
You HAVE to be able to charge the right cell count. A charger made for 7.2v is NOT good for 8.4v also.
Your charger has to auto-detect the end of charge of the pack. Various names are given to that: Delta-peak, peak-detect, fuzzy logic, delta-v etc. It is does not say, it most likely is not auto-detecting.
-You are looking are a charger around 50-90$ Anything under that will cause you more trouble than anything.
-NEVER shop for a charger in airsoft places. Go to your local hobby shop or hit internet. Avoid used or eBay unless you really know what you are looking for.
For Li-Po, you want all of the above to be included plus you need to have a balancer integrated to the charger. the other solution is to get an "interface" device that allows you to balance the pack WHILE charging.
A good one is made by Electri-fly (worth around 80$ by itself, and you still need a Li-Po charger).
E-Flight, Electri-fly, ThunderPower, Duratrax, Hyperion, Align are good brands for that.
It is a lot easier to find a good one on internet websites.
Be aware that there is more than one standard in the balance plug. Make sure your battery and charger have the same type.
Lastly, the no-go list.
Rule #1: If it is a whole lot cheaper than other brands, it is because it is cheaper. Same as with guns, there is a reason why CA, TM G&P are more expensive than CYMA, DBoy and JG.
Rule #2: "Smart chargers" are not a smart choice. These are amongs the worst chargers I have ever seen. Sure, they cost almost nothing. Ask Long_Bong what that little charger did to his battery in only 1 month. If you think your battery is dying and you use that charger, look no further, you battery IS dead.
I see a lot of misinformation on the boards since about 3 weeks.
Somehow, people start to think that since 11.1v is a bit too hot, using a LiPo pack that is under-rated will force the current down and thus reduce the damage to the mechbox.
Basic Ohm's law.
I is the current. This is the variable.
V is the voltage applied to the circuit. This is constant (since we are not changing battery as the motor turns or applying a wave form to it).
R is the resistance of the circuit. Unless you change the motor, this one is also constant.
Now let's say we compare a 9.6v 1400mAh 2/3A to a 7.4v 1200mAh 10C. The NiMh 2/3A will have a maximum current rating of 10C also, meaning that both have about the same maximum rating.
Our motor has a resistance of 0.5 Ohms with no load. (quite close to the reality actually).
I = V/R
I = 9.6v/5Ohm
I = 1.92A
This means that the current the motor will try to drain from the 9.6v battery is 1.92A when it is free-spinning.
I = V/R
I = 7.4v/5Ohm
I = 1.48A
The current that the motor will try to drain from the LiPo battery is 1.48A when it is free-spinning.
However, there is also a stall current that defines a motor power consumption and efficiency. Typically, that value is between 15 and 20 times larger than free-spin current.
This means that to start the mechbox, the motor will need around 22-30A for a split second. As soon as the motor start moving, that value drops until the motor reaches maximum speed. If the motor cannot drain enough current from the battery, the acceleration will be delayed.
Electric motors rely on electro-magnetic fields to work. The strengh of a magnetic field is dictated by the CURRENT that flows in the coils. This means that is the motor can drain only 10A and need 20A, it will produce only half the stall torque it could.
An normal NiMh battery will be able to deliver at MOST 15A in a peak, and around 10A continuous.
A normal LiPo (10C) will be able to deliver at MOST 30-35A in a peak and around 12A continuous.
Since stall current is only a fraction of second, the current draw is high for a very short period of time.
Here comes the problem.
We fire in semi-auto. This means that the motor will go in stall at every BB we shoot. On top of it, when firing full auto, each time the spring is released, the motor reaches maximum speed and is then decelerated very fast when the piston re-engages. This causes the magnetic field to be very light when spinning fast, and suddenly it requires to be very strong. Again, higher current drain (not stall current, but at least 5 times the free-spin current).
The way batteries work is not the same for all chemistry.
NiCd and NiMh cells have a very limited current rate. This is caused by the way the chemicals reach inside the battery. Even if needed, the reaction cannot be pushed past a certain point. Pushing it still generates a lot of heat, but since the components are fairly stable, a temperature under 150 degreesF is unlikely to cause an explosion. It will deteriorate the battery however.
LiPo cells are very different. There is two reactions at the same time that produces electricity. One is very active and the other is about the same as the one in NiMh cells. The problem is that the active one will not stop at a certain limit. It can accelerate as long as there is a need for more current.
That reaction generates a lot of heat.
Heat is the problem. The mix of chemicals used in LiPo batteries is a lot more unstable than NiMh of NiCd mix. Heating it releases hydrogen in large quantity. As you may know, hydrogen reacts with oxygen in a violent explosion and generates water. It is also a gas that causes pressure inside the battery. LiPo batteries are made from a Lithium film layed over a polymer core and folded over and over to form a flat roll. This is then wraped in a plastic sleeve, then an aluminum one and plastic again (for protection and insulation). Aluminum is a very brittle metal and is not expandable. This means that the protective sleeve can be damaged by the pressure build-up of the hydrogen.
This is when it can become dangerous:
When the pressure is too high, the sleeve fails and released the hydrogen in the surrounding air. This hydrogen is already very hot and now has plenty of oxygen to react with. The sleeve bursting is making a noise similar to a popped ballon, but is soon followed by a torch-like flame and the noise that comes with it. That flame is around 4000 degreeF or 2200 degreeC. It is hotter than a regular propane torch flame. To give you an idea, glass will melt and evaporate at that temperature.
The hydrogen burning is producing heat and water. Lithium is an alkali metal. It means that it reacts with water. The reaction with water is producing mainly hydrogen and also a lot (I mean a LOT lot) of heat.
This accelerates the burning of hydrogen (and supplies some carburant) and also releases a very toxic substance in vapor from the combustion of the polymer used in the battery. This can be easily be seen when watching videos of LiPo failures online. The white clouds are extremely toxic.
I have been exposed first hand to these vapors and have since some respiratory problems.
Again, please be extremely careful when choosing and using your LiPo battery.
Last edited by Kos-Mos; August 12th, 2011 at 14:49.. Reason: added info on Li-Po
|September 11th, 2006, 14:39||#3|
Join Date: May 2005
Location: Baie-Comeau, Quebec
I'd like to have some clarification on the following.
What is deep cycle?
How do you identify the type of cell your pack is using?
On my TLP fuzzy logic charger there is a charge option called "3 Cycles" consisting of :
Teamwork is essential; it gives the enemy other people to shoot at. - Murphy's Law of combat
""There are no atheists in foxholes" isn't an argument against atheism, it's an argument against foxholes." - James Morrow
|September 11th, 2006, 16:54||#4|
Join Date: Jun 2002
yes, that is a deep cycle
|September 11th, 2006, 23:09||#5|
You must know a bit about your pack to know witch kind of cell you have...
For example, mini packs (those 600mAh Ni-Cd they sell with the guns) are 2/3AF
AUG packs are 4/5AF cells
Large packs are Sub-C cells
Here is a list of dimension for each type
2/3 Sub C
4/5 Sub C
4/3 Sub C
Last edited by Kos-Mos; November 15th, 2006 at 03:51..
|September 12th, 2006, 01:20||#6|
Join Date: May 2005
Location: Baie-Comeau, Quebec
^^^^What is you measurement unit? Milimeters, inches?
Anyway, thanks for the precision.
Teamwork is essential; it gives the enemy other people to shoot at. - Murphy's Law of combat
""There are no atheists in foxholes" isn't an argument against atheism, it's an argument against foxholes." - James Morrow
|September 12th, 2006, 13:10||#8|
Join Date: May 2005
Location: Greater Grande Prairie (greater than vancouver)
on my g36 nimh 9.6 1200mah, and nicd 8.4v 1200mah
on my m4 9.6v 3600mah
is this procedure damaging or degrading my batteries? can you recommend a bettery process?
|September 12th, 2006, 13:36||#9|
Join Date: Jun 2002
Well you're basically cutting your usable battery life by 1/3rd. Battery cells have a certain number of charges in its usable life. NiCad I can't remember what it is, but it's around 1700 charges. When you deep cycle, you use up three charges.
|October 16th, 2006, 16:56||#10|
Is it possible to have the tread cleaned-up and Sticky? I think it might be of some use to most ppl.
I will add some infos about Li-Po soon too.
Done! Li-Po faqs is now on
Last edited by Kos-Mos; October 16th, 2006 at 17:38..
|October 16th, 2006, 17:31||#11|
Join Date: Aug 2005
Location: Saskatoon, Saskatchewan
Great FAQ, I'm sure I'm not the only one who appreciates the time you must have spent preparing it for the community, but may I make a suggestion? Would it not be beneficial to expand a bit on Amps as it relates directly to the type of cells used? I mean, the reason we cannot run a mechbox from a 7-cell battery consisting of 1.2v, 2200mAh AA cells is because the drain rate (Amps) is not sufficient. (AA cells having a drain current of ~2.1A, and Sub-C cells, for example, having a drain rate of ~30-40A)
It's not a terrible gripe, I'm just trying to distinguish an 8.4v, 2200mAh battery made from AA cells, with an 8.4v, 2200mAh battery made from Sub-C cells for those have less experience with cells, and undermine the importance of cell type. It's your FAQ, and your choice, hahaha, merely wanting to contribute is all. Again, great job, and feel free to use any of this out of context!
|December 29th, 2006, 01:58||#13|
Join Date: Jun 2003
Location: Montreal, QC
Hey all, just wondering if i could add a link to this thread. Pretty good site with a great battery charge calculator to estimate charge time.
|December 29th, 2006, 05:39||#14|
Join Date: Aug 2003
"Anyone with a name like Amanishourbariki should give a few letters to the poor Ng family." - Snarfangel, Fark.com
|January 9th, 2007, 20:22||#15|
I mean that in normal conditions (About 25░c ambiant temperature, no excessive humidity, no problems in the gun, charger, everything fine) the pack won't burst in flame for no reason. It will burst if you drop it and something tear the aluminium sleeve.