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View Full Version : Lithium ion conversion for longer endurance?


Hersker Hans
2009.11.06, 05:34 PM
I just ordered a few 3,6v 650mah li-ion batteries and want to convert one of my Mini-zs

The main reason for the conversion is that i want longer endurance and a nicer discharge curve on the batteries. the AAA have a lot of juice the first few minutes, then fades out slowly.

Is it possible to in some way transform the 7,4 volt from the Li-ion batteries to 5-6 v?, I could use a resistor to lower the amps a bit i guess, have anyone tried that? its also a bit waste of power to do that, a better way to lower the voltage would be nicer.

The point is that descent speed is ok ofcourse, but it is endurance i want.

yasuji
2009.11.06, 05:54 PM
I just ordered a few 3,6v 650mah li-ion batteries and want to convert one of my Mini-zs

The main reason for the conversion is that i want longer endurance and a nicer discharge curve on the batteries. the AAA have a lot of juice the first few minutes, then fades out slowly.

Is it possible to in some way transform the 7,4 volt from the Li-ion batteries to 5-6 v?, I could use a resistor to lower the amps a bit i guess, have anyone tried that? its also a bit waste of power to do that, a better way to lower the voltage would be nicer.

The point is that descent speed is ok ofcourse, but it is endurance i want.
just reduce ur throttle high point in ur radio;)

Hersker Hans
2009.11.06, 06:55 PM
just reduce ur throttle high point in ur radio;)

very good point, i use 2,4ghz. Could try training mode the first time, might just be fast enough. I kind of want the same speed as i have with AAA and atomic ar030 motor, just longer endurance and lower weight :)

addicted
2009.11.06, 06:55 PM
i want to make an extreme lipo chassis, so if you got any more details + pics then feel free to post them so i can look at them later :D

CristianTabush
2009.11.06, 06:58 PM
Stick to a PN70 turn motor and the power should not be uncontrollable. It will actually be quite nice. There would be no need to reduce your throttle end point either...

Hersker Hans
2009.11.08, 02:22 PM
is the PN70 motor a stock motor?

Hersker Hans
2009.11.08, 02:25 PM
i want to make an extreme lipo chassis, so if you got any more details + pics then feel free to post them so i can look at them later :D

ill post pictures when i start converting, and hopefully a video on how it works.

I wonder if the 2,4 ghz board takes more voltage than the AM board maybe? Ill try the AM board first I think and then convert my last AM miniz to 2,4 if i Fry it :)

wildthing
2009.11.08, 04:00 PM
same question... will the board handle the lithium ion power which is nearly a volt higher than the nimh batteries?

BTW I did saw a picture of a Lithium Ion powered mini Z in from an Atomicbuilt mini Z - http://www.atomicmods.com/ZoomImage.aspx?productID=10990

Traveler
2009.11.09, 07:09 AM
Its a lot more than 1 volt difference. 4 NiMH = 4.8v, 2 LiIon - 7.4v. But YES the board can handle it but most drivers can't control it.

Action B
2009.11.09, 03:05 PM
I have a lithium kit in my AWD I use sometimes. I run the lithium with an old PN 70 turn and it is still very fast. I do it for weight since it lightens up the AWD, but it also makes for great run times with very little noticeable reduction in acceleration. I will run them in every class that they dont' make me run Nimh.

Here is a thread I posted about my lithium conversion, pics are attached on my first post.

http://mini-zracer.com/forums/showthread.php?t=28081&highlight=lithium

Hersker Hans
2009.11.21, 03:56 AM
i got my batteries from atomic mods, and modded an AM tx rx Mr02 right away, im very happy with how it works with the stock engine, i guess i can drive 2 to 3 times longer now, and have a smoother curve. Ill check more precicly later.

I didnt remove the old batteryclips for the aaa batteries, i just undid the the two leads going from the board to the batteryclips on the rear of the car, and left them hanging loose, and soldered the new micro dean plug leads on top of the old wires going from the board,

I can just stick the old wires back in a minute if i want to use triple aaa batteries on the same car.

wildthing
2009.11.21, 05:14 AM
hersker did you us a cylindrical lithium ion battery or the typical flat lipo battery for your conversion?