These batteries are my first step into more powerful and expensive batteries. I have several batteries that are puffed up from drawing too many amps from them. I knew they were under powered but they were cheap. Now it is time to step up my game into batteries that are more sized for the size of motors and ESCs that I'm flying. My friend actually suggested trying the Giant Power batteries because he used them a lot in his RC boats. He also said that boats punish batteries more than quadcopters so he thought these would be a good fit. When I started researching them, I found out that Giant Power is starting to focus on the high end drone racing quads. That is good new for drone pilots.
So far, these batteries far exceed my lesser rated "C" batteries. Lipo batteries with a higher C rating tend to hold their voltage at higher levels under load then drop quickly near the end. Because of this, you may have to raise your low voltage alarm a little to provide a little more time to return to home.
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You can get your own Giant Power batteries off their homepage here:
1500 mAh:
1300 mAh: