P.Y.Tang reveals tips on Tamiya LiFe battery charging
An exclusive interview with P.Y.Tang reveals tips on what he did to gain the extra edge from the Tamiya LiFe battery which he won the 2012 Tamiya Asia Cup in Korea. Multi-time champion in Tamiya Singapore Qualifying and 5th place A-Main finalist in GPX-TRF class 2012 Tamiya World Championships, P.Y.Tang shows us his know how in making the Tamiya LiFe more power, legally. P.Y.Tang send us an article as below.
"As requested by some Tamiya racers, I will be sharing some tips that I used during my experience running the Tamiya LiFe battery during Tamiya races. Those who want to try out these tips are welcome to do so, but not guaranteed it will work for all drivers which depends on many other factors not excluding track condition, weather condition, battery condition, car setup charging equipment etc. Basically the 6.6V Tamiya LiFe is not as powerful as the standard 7.4V LiPo, and these tips are purely trying to get a little more power on the battery .
The 6.6V Tamiya LiFe is consider a low power battery compared to the regular 7.4V LiPo. The low capacity of the Tamiya LiFe 2200mAh is also a disadvantage especially using a lower turn motor, meaning the power fade would be more noticeable towards the end of the 5-minute run when the capacity is running low. In order to get more "punch" or acceleration power from the battery, I would charge the LiFe at high amps, which I normally use 20amps. However, using high amp charge, the battery is easier to reach peak charge, meaning the capacity input might be lower than when we use lower amp charging. Low capacity will result in quicker power fade and to avoid this, after the peak charge using high amps, use a low amp (0.5amp or 1amp) charge as many time as you can to top up extra capacity. A few hundred mAh can make the difference and decide your final results! This method will make the battery more "full". To increase additional acceleration power, I would also heat up both sides of the LiFe battery to about 40-45degC surface temperature, before charging. This particular steps somehow conditioned the battery cells better before accepting charge. I find the Muchmore battery warming tray works well in heating up the battery, or sometimes you can use the tire warmer as well. In some races which battery voltage is not controlled, you might find charging the LiFe using NiMh mode to about 8.5V-9V, giving you the extra power, but this is not recommended as the battery cells will fail at anytime. This method usually does not work when most races controls the battery voltage, and this method is definitely NOT for LiPo battery as it may cause fire hazard!
Besides focusing on the the Tamiya LiFe charging, mechanical parts of the car, electronic setup and race mentality and preparation is also very important. Stay tune for my next article. Enjoy racing!"