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Voltage sag and heat

I have 5amp hour. 12s 25c batteries. Zippy compact. Everything performs fantastic at first. I’m riding, blasting up hills.

At maybe 20 percent of battery capacity I will go up a steep small hill and the temp jumped to 190f. !! I think voltage sag is the cause. I didn’t have the torque or speed I normally have at that point and I can feell it…and ultimately I think with my finger still pulled down on the trigger it compensates with amps while the battery voltage sags, to get the watts I want to go up, the hill.

High c cells, or large packs, …I prefer making a giant battery and wish I’d bough more 18650s at 3500 on es.

I have the nanotech 90c pack to compare it to! As soon as I get another xt90s plug


I’M using the same Zippy compacts. There cheap batteries. I am also using them in series for 12s. I have noticed that they drop voltage fairly quickly. And sag even when bench testing! I have 3 12s sets so I change them out usually when they drop to 44v just to be safe. I used to have 4 sets but I ran a little too long and both batteries bulged and where ruined.
Eventually, I’m gonna see about switching to a pack of 18650’s

I found out w voltage sag the amps don’t compensate. U get less amps.

At 25% remaining they lose their Umph these batteries. Pretty good though. I likem

The bad news. The reason the motor is getting hotter than my last one is the blue thermal epoxy. It doesn’t help. Du. Thought it would and one thing led to another and didn’t put my board together to test the potting and du. So they run l10 to 15f hotter. I ran the same route as I’d done on video and posted it to endless sphere. In it I get to the top and measure the temp at 140f and then after coming back down on the brakes it was still 140f and I say so. I get 150 and 155 running it with these motors. I do it much faster though :blush: With the 80kv.

Anyone who’s getting any from me got 80kv and a smattering of random unknown 90kvs mixed in. Don’t ask why just trust that regardless of the blue goo and the mixed kv…these things still rock. <img

Why is because my inductance meter doesn’t work with the rotor on and once it’s on I’m not pressing it off to check and find them. My fingers are sore. And yesterday someone doored me and strangley the last half of the last pinky knuckle took the blow. Guy got out of the taxi stepped right over my batteries from the transmitter broken and walked in the hotel. Black guy was screaming at me that he would’ve kicked his ass and the taxi driver is yelling at me to sue him src="/uploads/db1493/original/2X/1/1a2aa151487d0b6315cd6e5b18102e570239bc5d.jpeg" width=“375” height=“500”>