Originally Posted by Ikraj, radiocontrolzone.com

There is one thing I want to clarify about matching. Many of you seem to believe that the 0.9v cutoff is an "industry standard" and that is a misconception about the battey business.

What I am about to write is not to offend anyone nor is it to say that one way is better than another. What I will try to do here is educate most of you as of what battery matchers do so that you can make better educated decisions when purchasing batteries.

First of all, there are NO BATTERY INDUSTRY STANDARDS set for the R/C industry. If we would have them there would be a standard designation. For example, we could have an IEEE or an ISO designation. We do not have either nor do we follow any standards. To set standards, the cutoff voltage is not the only thing that needs to be taken into consideration. There are so many items that set standards so that every one would follow the exact same procedures and techniques. For example, we would have to set a machine calibration standard, a power supply current standard, enviromental temperature standards, battery temperature control, and the list goes on and on. I am not going to write a battery standards essay here. What we have in the R/C business are not STANDARDS but similar procedures that matchers follow. Most of the matchers use the same machine to test. However, calibration, maintenance, and the way they operate are very important. These machines are measuring voltages down to the millivolt and it is so easy to be off. So, are you really getting a 1.185 or is it a 1.179 or 1.187 or 1.182 and so on...Since there are no SET STANDARDS even when several matchers show the same procedural methods on the stickers (by their numbers) that does not mean that you are getting an accurate reading for comparison between companies and sometimes even within the same company.

There are matchers out there that take very good care of their equipment and do try to control as many variables to get consistent readings, but even these vary from company to
company. My point is, are you really getting what the numbers say...I leave that to your decision. Based on my experience I think not...and I have bee doing this for over 25 years. One thing I have found is that with the quality of the cells and because there are so many variables, a pack that is matched at this moment may not and will probably not be matched in a few cycles.

I think that the best way to evaluate your batteries is by performance...you know which are your better packs... I have seen packs with lesser numbers be superior to better numbered packs. To keep a packed matched means continuos testing and rematching of your batteries on an ongoing basis.

Can we really use the numbers to compare battery packs, only you can answer that. I am not going to be biassed or try to force my opinions upon you, all I am trying to do is give you some known facts. I have answered so many questions regarding battery issues and some of you have very interesting questions. That tells me that your curiosity is there and that is good. The only way that battery matchers will obey and set a standard is if the consumers demand a standard. If you would show the lack of interest and you would not overpay for what some people call 1.185+ (or whatever) maybe the industry would shift and align itself in the right direction.

I call for the battery matchers to get together and establish a standard so that the consumer will benefit. I have wondered many times why this has not been done. You think about it. Come to a conclusion why nothing has happened over the last 20+ yrs.

I believe that it is time to set standards so that buyers can compare on an equal basis the quality of batteries, but the way our industry is I doubt that will ever happen.

Please note that this is only an opinion. An opinion based on knowlege and facts, not on hypothetical and uninformed thinking.

Hopefully most of you will understand where I stand and what I believe. This is not because of issues that would benefit me or my business involvement, but in the contrary. I say this to benefit the people that spend their hard earned money on batteries. You desrve better and maybe then a lot of the confusion about whom to buy from and what is better will be over with.

Originally Posted by Ikraj

In my opinion, there is a major problem matching batteries at a constant rate, and I will tell you why. There is a formula that states that E=IR which means, Voltage=Current X Resistance. Now if we manipulate this formula and look for current (I) the formula becomes I=E/R. R is a constan, by that I mean that R is the internal resistance of the motor, battery pack, wires, Esc...) and in all cases that should be used as a constant resistance. Being such, as the voltage decreases in your pack the current will decrease. If at the beginning when your battery is able to provide 1.215+V (as an example)and you are pulling 30Amps that means that the R that the battery sees is equivalent to 0.04 ohms. Now, at the point when your pack is down to 1.15V it can only supply 28.75A, when it gets to 1.0V it will supply 25A and at 0.9V it will supply 22.5A. do you see what happens, a decrease of almost 8 amps with less than -222mv (-0.222V.) We call that DELTA I over DELTA E (the changes of current/the changes in voltage) Our system has taken that into consideration and we use a similar load to evaluate a cell. We try get as close to race conditions as we can, there are other things that we do every x seconds but that is our secret... By testing and equalizing cells under the Axxis Hysteresis system we achieve a steady state condition in the batteries in order to get the highest HORSE POWER possible. As you can see I am not looking at numbers and voltages to match batteries. Like you said, its funny how the numbers are at times so close yet you can feel the difference in performance...There are very honest matchers out there that their numbers are very close to what the batteries actually do, but in reality these numbers do not mean much. They are basically a means of comparison. When a battery is matched over a 24-48hr cycle it is almost impossible to get very accurate and consistent numbers.

Now, the way that you have decided to buy your batteries is the right way. You found someone that can give you batteries that you feel comfortable with when you are racing, not when you are looking at the numbers. To me, that is the best way. Even if his numbers are way off and lower than others, his batteries perform, and that is the most important factor. At Axxis Racing we are doing everything we can to provide our customers with batteries that perform, regardless of numbers. Our batteries do not have numbers on them...when we test we come with a factor that we use (a number based on many variables). These numbers take into consideration many variables including but not limited to, charging current, voltage at different times, IR at different times (not only at the 2 min mark) etc, etc... Based on these numbers we put packs together. Now, one battery might be a 438 another a 432 another 419 etc...based on Turbo matcher numbers...but when we put the pack together we are looking at the overall performance of the pack as a whole not as individual cells. That is what makes Axxis Racing different from other battery matching companies. Our sysyem looks at the entire pack as a whole into consideration, not individual cells. Using the VOLTAXX Hysteresis system we can measure this and thus try to give our customers batteries that will perform and last. This system is much more easy on the cells thus you get a longer life out of your pack.

Originally Posted by Hick

I am gonna go out on a limb here....

All the batteries recommended here are good, very good.

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Though they are not labled or matched they are guaranteed 1.18 volts minimum. They are comparable to the ones recommeded here. Have trouble with them, don't meet advertised voltage, it's simple, return them!

Originally Posted by rcguy2477

They may guarentee 1.18 voltage, but that is at a 20 amp discharge as suggested by their listed runtime. Most matched batteries will run 1.2+v at a 20 amp discharge.