Lipo batteries in scale boats.

[785boats]

For those contemplating using Lipo cells in your scale boats with your existing brushed motors & ESCs here's a little gizmo that monitors the voltage of each cell while under load out in the lake & lets you know when to bring in the boat before damage occurs by over discharging.
Very few brushed ESCs have a Lipo cut out facility.
A lipo Sheild device works on 'forward only' ESCs not reversing ones, although Dimension Engineering is developing one that does.
Polyquest has one that cuts out at 2.5 volts per cell, but I think that's a bit low. I like to set mine in my brushless setups at 3.1 volts & would prefer the same in scale boats, or at the very least 3.0 volts.
I haven't tried one yet but as I'm starting to use Lipos in my scale boats it might be a cheap insurance policy.
Does anyone know of anything better that will work on all existing brushed ESCs?
See what you think.
Paul.
http://www.r2hobbies.com/proddetail.php?prod=rcps81934&cat=43

[smart_racer]

I use the GT Power portable digital battery meter...good for 1 - 6 cell li-po's...cycles through each cell giving voltage, and total pack voltage...about $5.00 at Hobby City

[Kmot]

A lipo Sheild device works on 'forward only' ESCs not reversing ones,
Hogwash! :p

http://www.teamnovak.com/products/lipo_cutoff_module/index.html

[Rob_P]

It looks like it connects to the Li-Poly's balance connector.
Not all packs have balance connectors and it needs to state who's connector its compatable with as these vary from manufacture to manufacture.

PS - Its not just a case of getting a plug converter as I believe the wiring schematic is different between manufacturers.

[Ghost 2501]

just a question...

with scale boats requiring ballast to sit them right, why go for li-po types in the first place? surely a heavy lead gel or ni-cad pack would be better, as with the lipo you are defeating the point of buying a light weight battery by adding the ballast?

[nick_75au]

Im considering lipos in my scale Kingfisher cruiser, for the discharge capacity, the Pb batteries fade out. I need to let the boat sit for several minutes before another speed run. Where space is at a premium they are also good. as an example I can get 4 6000 mAH 6S batteries where one of my 12v 12000 mAH Pb's sits with twice the voltage and 4 times the capacity.
Regards
Nick

[Ghost 2501]

ni-cad / ni-mh's?

[steveciambrone]

What is a PB, never heard this acronym.

My opinion:
For displacement hulls, tugs, freighters, and etc. no real benefit, usually they have a large hull with a lot of space for batteries, and ballast is usually needed for stability and scale waterline. Might as well use batteries instead of lead and make the weight useful.

For planning hulls, PT boats, runabouts, and racers. These all benefit from lighter weight, a lighter model will begin to plane at a lower speed and the top speed will be greater. These boats need no ballast, even for proper trim the Lipo can be moved around to adjust.

Thanks
Steve

[Ghost 2501]

pb- periodic table initials for Lead.

[785boats]

Thanks Tom for the heads up on the Novak brand of cutout module.
The Dimension Engineering brand (the LipoShield) is obviously a different setup.
I'll have to look into the Novak one.
Smart racer.
I have one of those too, but it doesn't protect your cells under load out in the water. Good for checking voltage between runs though.
Rob_P
Point taken about the wiring & plugs. Didn't think of that.
Ghost2501.
I must admit that I was thinking more along the lines of cabin cruisers, PT boats. Chris craft runabouts, Rivieras ETC Rather than the big displacement hulls. As pointed out by Steveciambrone.
Besides, I can buy good quality Lipos cheaper than metals, with higher capacity & higher current delivery capabilities than the metals. This gives livelier performance & longer runtimes with cooler batteries.
As my Ni-Cad & Ni-mh packs fail, I will be replacing them with Lipos.
Nick.
That should stop that battery fade problem for sure.
Steve.
It seems that we are basicaly of the same opinion.

I guess what I was really trying to do is suggest/find ways to protect The Lipos when using them on our existing brushed ESCs that don't have cutouts like the brushless ESCs do.
Cheers to all.
Paul.

[mfr02]

What is a PB, never heard this acronym
Should be Pb, short for Plumbum, Latin for lead, hence plumber, one who works with lead.
Something to add to the list of fairly useless information.

[Ghost 2501]

I get 40 mins with a pair of 3300ma/h ni-mh 7 cell packs doubled up to get 6600ma/h, and that is in my Robbe Najade, spending time on the plane. and she is still shy with ballast. a Lipo would still mean I would have to add lead to push the prop under

[Bob Bighinatti]

Hogwash! :p

http://www.teamnovak.com/products/lipo_cutoff_module/index.html

Just bought one for my Monaco to go on a Venom 5400 3s battery. willlet you know how it works .
Bob Big :) :)