The most common mistake in charging a LiPo.

Your LiPo battery must have two connections made to charge properly. First, you must connect the two conductor wire with the banana pins on the charger end and the Deans or JST on the other. All of the charge to the battery goes in this way. If it is not connected, you will see an error message about a bad connection.

The other connection is for balancing. This is the small blue board for Thunder Power cells with a number of connectors on the board and a wide connector that plugs into the charger on the same side as the banana pins. Power is REMOVED from the battery for balancing. The charger will detect the cells with the higher voltage  and draw current out of the battery to bring these cell voltages down to the level of the lowest cell. No charge is ever put in to the battery through the balancing connection.


Why Balance?

When LiPo batteries first became available, no thought was given to balancing. Over time, the individual cells in a battery could change voltage. The weak cells would keep getting worse and finally, the battery would only charge up to the required voltage by over charging the good cells. When this happened, the battery would seem to charge, but fail quickly when put into use.

For a good number of years all LiPo battery manufactures have added a special connector to allow the battery cells to be charged to the same voltage. Similarly, the charger suppliers have added this new feature to their products. Any charger that does not have balancing capability, is obsolete and should not be used. All reputable LiPo battery makers include the balancing wire and connector. This costs them added money and in a competitive world they would not do it if it were not important. Be sure your charger has this capability. You may have to go to your hobby shop to obtain the necessary balancing board with the suitable connectors for your brand of battery. This will cost you less than $10. If you obtained your charger from us, it comes with the correct balancer. And a second generic one.

I have heard of fliers cutting off the balance wires and connectors to save a gram weight. This is Wrong and do not do it, unless you want to reduce the life of your battery and limit the performance in a contest. Always balance when charging and even check the individual cell voltages when the charger says is it done. You should find all cells to be within 0.02 volts of each other.

Battery Characteristics

As received, the Thunder Power battery from us will have about a 50% charge in it. This is pretty standard for all LiPos. It turns out that all batteries with this chemistry store best with a 50% charge. This means when putting the battery up for the winter or long term storage, you should discharge it to the half charge level. How do you do this? Well this is not exact, but charge it up and then put it through two 15 second run cycles with the 1806N and a 7.5X4 prop. This will get you close.

You have all learned the the Nicad and NMHd batteries need to be cycled or run all the way down before charging to get the most out of them. This is true for them, but NOT the LiPo. They have no memory and there is no need to cycle them. A new LiPo needs to be conditioned when new by not hitting them too hard with large loads  for long times. (sound like what we learned in the 50s about a new car doesn't it?)

Charge your LiPo just prior to a contest flight to get the absolute most out of it. I mean just before you fly, not the night before. The charger we sell is great for this as it is lightweight and can be used at the field.

How to Charge

Although you can charge at a rate of 2C (twice the battery rating, in the case of our TP 325 mah battery this is .65 amps or 625 ma) BUT, this is not recommended if you want the best life. Charge only at 1C or .3 amp (325 ma). We setup our charger for a charge current of .3 amps or 300 ma before it is shipped. A completely discharged battery would take just over an hour to charge. But, in real life, you are not taking that low, or we sure hope so,  and it will recharge in 20 minutes or less. If you have two batteries, then fly with one while the other is on charge.

Discharge Warning

LiPos must never be fully discharged. If this happens, the battery is toast, gone, lost. Do not try to use it. The ESC has a programmed safety in it that prevents the motor from running when then battery falls below a set voltage. We set this voltage high when we sell a Plug N' Fly kits to be sure you take good care of the battery.

This is important. An ESC will draw power from the battery, even when the motor is not running. This standby current is normally in the 20ma range. The safety shutdown does not work in this situation. So, if you leave the battery connected to the ESC for a day, chances are the battery is ruined. You may think it is charging, but it is not. It will die as soon as you start the motor. I unplug the battery as soon as I pick up the model after a flight.  This is a good practice to follow. We do not recommend you put a switch in as one that is good enough to not cost you power is way too heavy to use in FF.