Electronical help needed...

Help!

The little Kilo is so cramped in the stern section, I just know I'm going to break something trying to stuff a four cell AA battery pack in the space I have, so I'm thinking about buying a LiPo pack, as I think these are smaller than a conventional nicad pack...are they?

What I need to know is : I run the whole boat (rx, esc, two micro servos and the motor, a 280 sized one) from the battery pack, so can I still do this with a LiPo pack?

What voltage do LiPo's come in? I need something between a minimum of 4.8v and an absolute maximum of 6v (when fully charged)

Help gratefully received...

Richard
are you talking about putting a lipo in the free flooding area?

Lithium polymer+Water=BOOOOOM

Hi Richard

A lipo pack voltages are
3.7 volt for a 1s
7.4 volt for a 2s the actual voltage fully charged is 8.4
11.1 volt for a 3s the actual voltage fully charged is 12.6

the voltage of the 2s 7.4 volt pack is as close as you are going to get to 6 volt
one way of using a lipo is to find a speed control with bec
The bec in a speed control will be able to handle the motor and 2 servos no problem.
Lipos come in all different sizes from very small have a look at this link and click on different packs and you will find the sizes as well

http://www.giantcod.co.uk/cell-lipo-battery-c-1_113.html

I have used loongmax lipos from giant cod for long time had no problems
I have had a lot of stuff from giantcod for my aircraft no problems
One other way is to use a ubec
I have all ways used hobby wing ubecs in my electric aircraft with a power input to the motor on 6s 22.2 volt of over 1000 watts no problems at all

http://www.giantcod.co.uk/ubec-c-21_76.html

hope this helps any questions I am more than happy to help Geof

Thanks Geoff,

I'm reliably informed that I can't put LiPo's out in the free flood area though...see above from Nigel.

These seem to be the highest output AAA sized batteries I can find.. HERE

Hi richad

sorry about the post above i was writing it and posted it will every one had given you the awnser

you could try overlander i have got a very small 4 cell 350 mah nimh pack couple of those may do the trick there so small
or try this one 800 mah enelope

http://www.overlander.co.uk/sanyo-eneloop-800-aaa-6v-rx-hump-pack.html

enelope are sopposed to hold there charge for a long time not like nihms that go flat fast on there own

all the best geof

I ought to say that my info on lipo's is well out of date now,and thing's could well have changed but I will tell you the story anyway,some years ago when I worked for a well known model shop a rep came in and asked me if I would run lipo's in my submarines if he supplied them free of charge so that his company could use the advertising,what he did not know was that I had seen a helli with a lipo get caught in a storm and the lipo erupt in to a flaming ball,so I said to him I was not interested but he persisted so in the end I said to him tell you what throw one in a buckett of water,so I went and got a buckett of water and we adjorned to the forcourt and he trow this lipo in and it was fine,we left it there for age's no problem,I was on the point of changing my mind when my collegue said to me that the lipo in the helli that caught fire had a small tear in the outer cover,so I asked the rep if we could put a nick in the cover of the one we where testing he said yes he was confident it would make no difference,so we put a tiney nick in the cover dropped it back in the buckett and sure enough all seemed fine,then there was a slight fizzing noise then a boom and a flash,no buckett no battery and no trouser leg,and a guy riding past on a bike jumped and rode into a lamp post,exit very emmbarased rep.But as I say this is a long time ago now things may well have changed.

Hi Richard, in my 214, I used an aircraft speed controller with BEC which was tiny, but obviously I only have forward control. Also as you are using only 3 channels, try looking on aircraft sites for mini receivers. This may give you more space inside the tube, or allow you to make the tube smaller, thus giving you more wet space. If you can fit AA cells then battery capacity would not be a problem, I have 6x1100 mAh NiMH in my 214.

Roger

Have a chat to these guys they are great and will tell you all you need to know about batterys.

MODELPOWER 01827-711501

I'm going to have a word with Steve Neill later on, he managed to squeeze a full static dive system into his Kilo.

You may be able to use Lipos outside the WTC but you will need to do a bit of R & D (And tell us what happened!)
I have used a 1700 mAH lipo in the Holland for several years but this is inside the WTC. Mind you if it flooded it would be in water.

Nigel advised me against Lipos and suggested that I try putting some in water. I had an old pack and I tried it. Nothing happened. But a nick or split in the outer plastic sleeve (as Nigel says) - maybe BOOM!

Against this - the advice to destroy old Lipos is to cut open and immerse in salty water. I've also read that there is no metallic Lithium present in a cell.

I know that Steve Neill has used them for many years. So maybe a combination of asking him + the manufacturers could do us all a favour, because they are very handy technology.