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BrianG · **RCM Lipo impressions -** 12.01.2008, 02:05 PM

I picked up a couple of Mike's new lipos (5s2p 5Ah 25c) and ran them around a little. I don't have an eagletree and the outside temps are a bit nippy, but they ran great!

After having problems with my GTP and MBX5/CORR conversion (blew ESCs), I decided to discharge the lipos for storage along with my 4s2p 5Ah Maxamps pack. But I figured I would do a little testing at the same time so I charged everything up fresh.

I use a custom CC discharge circuit (darlington transistors and power resistor setup) that will draw 10A from batteries ~10v up around 5s (the transistor and resistor setup gets quite hot even with a fan at 5s - but that's 185w too). I hook up a balancer and use a voltmeter to monitor cell voltage to get to my desired 3.5v/cell storage level.

With the MA 4s 5Ah pack hooked up, that 10A load dropped the voltage by 0.48v. When it hit my 3.5v/cell threshold, it had taken out about 2300mAh. Various cell LEDS on the balancer (LBA10) would flicker on and off during this time. Removing the load brought the no load voltage up to 3.73v/cell.

With Mike's 5s 5Ah packs hooked up, the same 10A load dropped the voltage by around 0.08v (fluctuated between 0.07 and 0.08v). When my 3.5v/cell threshold was reached, it had taken 4.36Ah out of the cell. Cell 3 on the same balancer flickered for about 30 seconds once. Removing the load brought the no-load voltage up to 3.67v.

Cell resistance is not linear so you can't really say how much voltage will drop at the rated C value simply by using the 10A load and voltage drop figures. Yeah, it's not the best test, but it certainly hints at a lot as far as performance goes.

	(#1)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	RCM Lipo impressions - 12.01.2008, 02:05 PM I picked up a couple of Mike's new lipos (5s2p 5Ah 25c) and ran them around a little. I don't have an eagletree and the outside temps are a bit nippy, but they ran great! After having problems with my GTP and MBX5/CORR conversion (blew ESCs), I decided to discharge the lipos for storage along with my 4s2p 5Ah Maxamps pack. But I figured I would do a little testing at the same time so I charged everything up fresh. I use a custom CC discharge circuit (darlington transistors and power resistor setup) that will draw 10A from batteries ~10v up around 5s (the transistor and resistor setup gets quite hot even with a fan at 5s - but that's 185w too). I hook up a balancer and use a voltmeter to monitor cell voltage to get to my desired 3.5v/cell storage level. With the MA 4s 5Ah pack hooked up, that 10A load dropped the voltage by 0.48v. When it hit my 3.5v/cell threshold, it had taken out about 2300mAh. Various cell LEDS on the balancer (LBA10) would flicker on and off during this time. Removing the load brought the no load voltage up to 3.73v/cell. With Mike's 5s 5Ah packs hooked up, the same 10A load dropped the voltage by around 0.08v (fluctuated between 0.07 and 0.08v). When my 3.5v/cell threshold was reached, it had taken 4.36Ah out of the cell. Cell 3 on the same balancer flickered for about 30 seconds once. Removing the load brought the no-load voltage up to 3.67v. Cell resistance is not linear so you can't really say how much voltage will drop at the rated C value simply by using the 10A load and voltage drop figures. Yeah, it's not the best test, but it certainly hints at a lot as far as performance goes.