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wolfdogstinkus

My introduction to lipo

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I recently decided to make the move to lipo, without knowing much about what I was doing, I rushed out (onto ebay) and bought two lipo's and a charger.

The charger never arrived ( had to open case on ebay) so I ordered another charger from modelsport uk yesterday and it arrived today.

The charger is an Orion advantage IQ404 which charges at 5A on 2s and 3.3A on 3s. I also have a Lipo safe charge bag.

The lipos were a bit bigger than a stick pack, the 2s fits in the DT-02 and the 3s is for the blitzer beetle, the 3s is a bit wider than a normal stick pack so here's what I have done,.........................

DSCF5494.jpg

I think this is a soft cell pack so I decided to pad it out with carpet underlay, is this a good idea?

DSCF5495.jpg

And made a new battery strap to hold it in,

DSCF5493.jpg

DSCF5496.jpg

All wrapped up and strapped down.

DSCF5498.jpg

Massive improvement over my old ni-mh batteries, I was thinking that the extra 0.2V on a 2s wouldn't make any difference, but I was very wrong,

I have to do some more testing but I will report back.

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welcome to the future , aka the standard now :)

for the blitzer the turnigy 4000 2s hardcase fits perfectly , i have some 5300 hardcase nanotechs on the way , that should fit too.

i would recommend to use hard case batteries in cars , much safer , also you dont need the padding. how flammable is that carpet padding ? in case the lipos start too smoke it might fuel the fire .

also , i recommend that you do the blitzer shock reinforce brace since you havent done it yet. really simple but effective

EDIT

hobbyking germany seemed to got a descent supply of Hard case lipos , they didnt last week when i ordered mine in hongkong, just get the higher C rating ones and you are good :)

http://www.hobbyking.com/hobbyking/store/__411__85__LiPo_LiFe_NiMH_Battery-Car_Hardcase_Packs.html

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Would you recommend removing the padding then atf300?, not sure how flammable it is but if it catches fire in the car it will allready be too late. I thought the padding may help to reduce any hard impacts. I wouldn't use it while charging.

This is insane now, does standing backflips. :D

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if its super flammable then remove ,but i only use hard case lipos so cant judge on that . i've seen guys use homemade lipos with no padding at all in boomerangs , hot shots , grasshoppers etc . never have i seen a lipo fire in real life though .

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THe thing with lipos is IF they were to go up in flames a bit of padding isnt high on your list of concerns. There is no putting out a lipo fire it goes out when the fuel supply (lipo itself) runs out. But after saying that Lipos are very safe to use if you look after them.

You should be ok with the batteries in those cars as they are, a bit of padding is a good idea if the packs dont fit fairly snuggly in chassis. Non hardcase batteries are fine in a car as long as like blitzer and DF the chassis forms a hardaces in itself.

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This is cool, brushless motor, highend ESC + Lipo and a vintage 27AM receiver. Nice ;)

do you have a failsafe built in somewhere with all that power inside?

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This is cool, brushless motor, highend ESC + Lipo and a vintage 27AM receiver. Nice ;)

do you have a failsafe built in somewhere with all that power inside?

I think the transmitter or ESC has a failsafe built in?. Edit, I am sure the ESC has built in failsafe

I did try to set it up with my new 2.4ghz radio set but the ESC didn't like it, it may have been because my trims weren't exactly central. I might try to set it up with the 2.4ghz radio again when I have time. But thats the reason for the old transmitter.

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Welcome to the lipo club, i resisted for so long and having made the change over i wouldn't go back for anything.

I just been out trying to keep the DT-02 rubber side down on the 7.4V 2s, :lol: It's not easy. Now where can I find a speed camera?. :D

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I made a couple of mistakes while making the change to lipo, (I make mistakes so you don't have to)

First was to not do enough research and bought soft case lipo's, I am still waiting for a imax b6 charger from hong kong, should have checked sellers feedback more carefully.

I soldered my deans connectors on the wrong way, don't know why? or where I got the idea from, but I soldered the male ends on the battery and then decided it was a bad idea to have live connections protruding after I had done 2 ESC's and three batteries. DOH!!!!!! All sorted now. The female ends are on batteries and male ends on the ESC's.

I left the red heatshrink on the floor and my kitten savaged it, it is now full of claw and teeth marks.

I will have another go tomorrow, not tried the 2s in the blitzer yet but the 3s is just crazy fast with loads of torque.

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when did you order hong kong, it can take 6 to 8 weeks and then if your 'lucky' it gets stuck at customs. :unsure:

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It was over a month ago, I have opened a case on ebay, the seller has quite a lot of bad feedback about delivery times but postage wasn't cheap so it's a bit annoying.

I ordered one from modelsport uk and it came the very next day, I wish I had done that in the first place.Will it be delayed by customs even with a low value item? I am in U.K.

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you do know that you should always balance charge lipos when possible , it prolongs their life greatly

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Hi atf300, yes my charger does balance and I have charged with the balance lead connected.

@Speedy w beans, thanks for the link, I think I have all that covered now, just thought if I write down my experience it may help others

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get these

They'll fit in any car designed to take NiCds. I've put them in TA01 FRPs TA02 tubs and TA03's. No padding needed.

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Those Jamara hard case round edge packs are identical dimensions to a Ni-MH/Ni-Cd pack and will fit anywhere they do. These are 134mm long.

I've been using IP4000 hard case round edge packs. These are the same dimensions around the pack as a Ni-MH/Ni-Cd, but they are 138mm long.

The 138mm long pack will fit into the Blitzer chassis without issue. In the DT02 chassis you need to trim 3mm from the little ribs at the front of the battery tray for the 138mm long packs to go in.

Using soft packs is very risky in an offroad surface vehicle. The jarring from landing a jump or a rollover is enough to distort the soft pack which will cause it to short internally. Most Li-Po fires in planes/choppers (uses soft packs) is from the impact into the ground after they fall out of the sky.

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Thanks for your input Sayer and TA-Mark,

What happens when these soft case batteries swell?, Is it visible to the naked eye?

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I just been out trying to keep the DT-02 rubber side down on the 7.4V 2s, :lol: It's not easy. Now where can I find a speed camera?. :D

alright Wolfie

i take it by switching to lipo it makes your car faster?

is this the same if using brushed motors?

just been having a look at lipo,s on modelsports site and i see hardly any use tamiya connectors.

my ESC is lipo compatible would i have to change the tamiya plug for deans type?

cheers Karl

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i take it by switching to lipo it makes your car faster?

Yes! Li-Po are 0.2 volt more (nominal voltage), and there is much less voltage sag under load. Higher voltage will make the motor spin faster.

is this the same if using brushed motors?

Motor type makes no difference. Both are faster on Li-Po because of the reduced voltage sag under load.

just been having a look at lipo,s on modelsports site and i see hardly any use tamiya connectors.

my ESC is lipo compatible would i have to change the tamiya plug for deans type?

The electrical system works like this: The motor will determine how much amperage will be drawn through the system. The ESC needs to be rated for this amount of amerage or it will run hot and thermal, or worse, fry. The wiring and connectors need to be able to handle the amount of amperage passing through them, or they will get hot and melt (and sometimes melt so much they will melt together and short the wires). The battery needs an output amperage that will supply what the motor asks for. Unbalance any one of these and that componenet will run hot, including the battery pack (motor heat is different and closer related to load - the amount of amperage it's using constantly).

In a practical application. A RS540SH Mubuchi silvercan will draw 57 Amps at stall (most amount of load). The TEU101/104BK ESCs are rated for 60 Amps forward. A Ni-Cd is lucky to be able to supply 20 Amps, and the best quality race Ni-MH packs around 40 Amps. The poor Tamiya plug in the middle is rated for 7.5 Amps (when it's in new condition and makes a good connection). From this you should be able to see that the Tamiya plug is a bottleneck even with a standard setup. Add a hotter motor which draws more current (amperage) and a higher rated ESC, then switch over to, say, a common 100 Amp 25C 4000mAh Li-Po, and the poor molex style Tamiya plug is way out of it's depth. This is why high end ESCs and high power battery packs come with high voltage plugs. A deans plug is rated for a continuous 100 Amps. If the pack or ESC don't have them factory, it's a very good idea to ditch the Tamiya plug and fit something better.

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<p>Hi Flexus, I don't understand the science, it may just be that my ni-mh batteries were well past their best?, but they never lifted the wheels on any of my cars.

The dt-02 on 2s 7.4Volts is crazy, I wouldn't say it is a lot faster top end but the punch and acceleration is crazy, I have actually considered turning down the punch on the speed control for the first time ever.

The charger was £29.99 and in stock so it arrived the next day, I made a mistake by getting soft case lipo packs but a decent hard case can be had for around £25.

I would say it would make your brushed motor much faster, it's a bit late at night now but I can try it on a brushed motor tomorrow and report back for you.

The tamiya connector is rated to 7amps, I think?, even the 9t ezrun puts out 35amps and more so the tamiya connector is the weakest link and it will melt together and become useless, the deans connectors are a solid brass flatbar which is rated much higher for brushless aplications, a worthwhile upgrade even with a standard silver can as once that Tamiya connector wears out it can become hot and melt with the stock equipment.EDIT, ninja'ed by TA-Mark

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What happens when these soft case batteries swell?, Is it visible to the naked eye?

Very obvious. The soft covering will swell up like a balloon with the gas build up inside the pack. Do not attempt to charge a swollen pack.

The same happens in Ni-MH and Ni-Cd packs when they build up gas pressure inside. The +ve end of the cell has small vents to let this pressure out. I've heard some of my older packs vent while being charged it can be that loud. When these vents become blocked (usually by dirt) the cell will explode (like a hand grenade or like throwing a pressure pack can into a fire).

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Yes! Li-Po are 0.2 volt more (nominal voltage), and there is much less voltage sag under load. Higher voltage will make the motor spin faster.

Motor type makes no difference. Both are faster on Li-Po because of the reduced voltage sag under load.

The electrical system works like this: The motor will determine how much amperage will be drawn through the system. The ESC needs to be rated for this amount of amerage or it will run hot and thermal, or worse, fry. The wiring and connectors need to be able to handle the amount of amperage passing through them, or they will get hot and melt (and sometimes melt so much they will melt together and short the wires). The battery needs an output amperage that will supply what the motor asks for. Unbalance any one of these and that componenet will run hot, including the battery pack (motor heat is different and closer related to load - the amount of amperage it's using constantly).

In a practical application. A RS540SH Mubuchi silvercan will draw 57 Amps at stall (most amount of load). The TEU101/104BK ESCs are rated for 60 Amps forward. A Ni-Cd is lucky to be able to supply 20 Amps, and the best quality race Ni-MH packs around 40 Amps. The poor Tamiya plug in the middle is rated for 7.5 Amps (when it's in new condition and makes a good connection). From this you should be able to see that the Tamiya plug is a bottleneck even with a standard setup. Add a hotter motor which draws more current (amperage) and a higher rated ESC, then switch over to, say, a common 100 Amp 25C 4000mAh Li-Po, and the poor molex style Tamiya plug is way out of it's depth. This is why high end ESCs and high power battery packs come with high voltage plugs. A deans plug is rated for a continuous 100 Amps. If the pack or ESC don't have them factory, it's a very good idea to ditch the Tamiya plug and fit something better.

Hi TA-MARK

thanks for the detailed lipo info mate.

your like tamiya R/C wikipedia. :)

cheers Karl

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