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By Energy 3200mah 25C Lipo from rcmodel.com.hk REVIEW
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fastbaja5b
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By Energy 3200mah 25C Lipo from rcmodel.com.hk REVIEW - 09.18.2010, 08:49 AM

Well I was chasing a cheap Lipo for the basher I let family and friends use when I'm out with the Summit. It's not an overly demanding car, HBX Cross Tiger which is essentially a TL01B with Truck Wheels, a HW 2.4ghz Radio, Bluebird Water Proof Servo, XL5 Waterproof ESC and a 550 motor geared the lowest I can.




Hardly a demanding motor!


Pack can be bought here:

http://shopping.rcmodel.hk/advanced_...sg1i00&x=0&y=0



Shows itself to be Tamiya Stick Pack size, that was the first mistake, took a lot of coaxing to slide into the battery tray, not sure about getting it out yet. Charged it up and left it to sit overnight, in the morning the Hyperion Sentry had it's voltage as 90% of capacity.


So how'd it do... one word. PITIFUL!

Total run time was around 12 minutes, 2100mah used before the Lipo Alarm went off (set at 3v/cell) Total recharge after this run was 2150mah, so 3200? Not bloody likely!

25C... well on a 50 amp burst this thing drops below 3v a cell and that was when the pack was "full" It's got as much punch as Bambi with a head cold.

Here are the Eagle Tree Graphs





In short, this pack is nowhere near as advertised, 3200mah is wishful (try 2000mah) and 25C is really pushing it, I'd say closer to 15/20C at best. It shows that many of these "cheaper" lipos are rated nowhere near what they claim to be.

Garbage!


Say Less, Do More.
   
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sikeston34m
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09.18.2010, 12:22 PM

Final Discharge Performance is a combination of ACTUAL capacity and actual C rating.

Actual capacity is often rated by the manufacturer by charging a discharged cell at a very low rate, then measuring how many mah was put back in. IMO, this is squeezing things to the limit.

Actual C rating is derived from how many amps the pack can sustain without dropping below 3.2v to 3.4 volts per cell.

Who's to blame for the inflated ratings? It's the either the manufacturer OR sometimes it's the retailer. Either way, the label is BS.

I'm thinking the pack you have, is 26650 Moli cells. It's not a lipolymer pack at all if it's using cylindrical cells. These cells are commonly found in cordless tool packs.

If the mah returned is only 2000mah, by looking at the charts, you have a 10C constant pack. I'm looking at a spike just past the 8 minute mark. 34.5 amp spike where voltage dropped to about 3.2 volts per cell.

I recently purchased a 10.8v 8800mah "12 cell" laptop battery pack because I needed 10 of the 18650 cells to rebuild a Craftsman C3 pack.

This should have given me 12 18650 cells that are rated at 2200mah each. Good choice for low drain devices such as lights, etc.

What I found inside the pack when I opened it up was:

9 - 18650 cells that are only 2000mah each
3 - dummie tubes to take up the extra space where the other cells should have been.

This makes the actual pack only 6000mah at best.

But it looks like a 12 cell on the outside because of the casing.

Clearly a rip-off.

What are they thinking? They will never know the difference?
   
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