The boat is still for sale. I neglected in my earlier post to say that pictures and a description of the boat are available on the following website: Home Thanks.
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Yeah I know, thats a lot of cells to solder together. But I was wondering if anyone had done this already. The reason I ask is because I have seen these Li-ion cells for as little as $1.25/ea, 6ah 3.7v. That's with free shipping from China. Now I know there are going to be a lot of substandard cells in a shipment of these things, but maybe the batting average would be good enough to make this cost effective (but not labor effective lol). But what would be needed would be a good routine for testing these things to weed out the duds and the weakies before soldering or spot-welding them together. It takes 13 in series to make 48v. So a series bundle of 13 paralleled with 49 more just like it would be a 300ah 48v bank, made up of lets see... 650 cells total. That's a lot of testing. So I am thinking some sort of gang/batch testing device and an efficient test routine. Maybe Arduino powered? I don't know. Like most of my projects I am starting out with near zero knowledge.
I am thinking about just getting like 26 of these cells and making a 48v, 12ah battery pack for the E-bike, just to get my hand in the game. That's $32.50 for cells and free shipping... just need some copper and a case and enough reserve cells to replace the inevitable bad cells, and I think I could be all in for well under $100, about 1/3 the cost of a typical e-bike battery.
Or maybe it would be simpler to make up parallel bundles of cells, then connect the sub-units together in a series of 13?
The only reason I am using golf cart batteries is cost. They are simply the cheapest way to go that will work. But 18650 cells would bring the cost down to not much more than the GC batts. Well, apart from a very "busy" BMS setup lol. But still, Im liking the numbers. To get a 220ah bank which is what I have now in flooded lead acid batts, I would need 37 parallel, 13 series, or 481 cells. At $1.25/ea that is $601.25. Lets say a 15% reject rate... still looks good. The golf cart batts are $85/ea for 6v, 220ah. That's $680 plus tax and core deposit. Even if the 18650 setup cost 50% more, it would still be worth it for the increased lifespan and greater depth of discharge.
Somebody argue with me here, because I think I might be too enthusiastic about this idea.
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Nice! Too bad they don't make BLDC controllers, too. I have heard good things about Alltrex.
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Might be better with a rib frame under them. A square tube would add strength and be lighter than a plate thick enough to add anything.
Thanks for the feedbacks Hannu and Mike!I guess I should glue a sheet/plate of aluminium on each of the panels to make them stiffer.BendikOn Wednesday, July 29, 2015 7:53 AM, "Hannu Venermo gcode.fi@gmail.com [electricboats]" <electricboats@yahoogroups.com> wrote:
No.
No experience with panels specifically, but nothing that size will last while vibrating in the wind.
They are just too thin to last, without a substrate or backing of some kind.
On 21/07/2015 08:46, Bendik Vignes bendik.vignes@yahoo.com [electricboats] wrote:
I have no experience with flexible solar panels, but many of you do - what is your opinions/experiences: are flexible panels durable enough to be mounted by the eyelets only?
RegardsBendik, Norway
-- -hanermo (cnc designs)
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Bendk
I would use something like Lexan rather than Aluminum. Though I really don't think it is necessary as long as the panels are not waving like flags in the wind.
Mike
I have no experience with flexible solar panels, but many of you do - what is your opinions/experiences: are flexible panels durable enough to be mounted by the eyelets only?
RegardsBendik, Norway
-- -hanermo (cnc designs)
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IF you put stuff in another site, 80-90% of people wont go there.
Most content, and the value of the community will be lost.
The nr 1 reason y groups work is that they come into my email automatically.
I would never go to another web-based, very slow, very clunky, site.
I read 200-300 emails every morning, from my groups.
Effortlessly, in 30 mins or so.
Web-based stuff would be a total non-starter.
Likewise, due to their policies, anything facebook is a no-no, for me,
and many others.
If the primary interface is mail-based, like these groups, and ..
its supported by a well-organised pictures-folder, and..
supports grouped downloads (full folders, by author, by subject etc), and ..
has sane content policies ie ownership of content rests with creator
then thats a different matter.
Do you realise thats a 1000+ hour job ?
Will it run on a proper server, with low latency for worldwide access ?
No ads ?
Coming from someone who used to own and manage a large network, with 70+
customer servers.
On 29/07/2015 09:01, salomefonseca@yahoo.com salomefonseca@yahoo.com
[electricboats] wrote:
>
> What does the group think? I'm game.
>
> Jerry
> Redding, CT
>
--
-hanermo (cnc designs)
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I have no experience with flexible solar panels, but many of you do - what is your opinions/experiences: are flexible panels durable enough to be mounted by the eyelets only?
RegardsBendik, Norway
-- -hanermo (cnc designs)
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I blew the phase A mosfets in my old Kelly KBL48301X controller a while back, and ordered a new KBL48501E controller as a replacement/upgrade, then sent the KBL48301X back to the factory for repair. Their tech guy looked at it the same day they received it and I got this in an email:
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Good idea Jerry, I think it would be very helpful.
Sal Fonseca
Paso Robles, Ca.
Building a Bruce Roberts Spray 36B
------ Original message------
From: Jerry Nevins jnevins@jnevins.com [...
Date: Tue, Jul 28, 2015 12:32 PM
To: electricboats@yahoogroups.com;
Subject:Re: [Electric Boats] Re: 31' Sailboat Conversion
Hi! I did a conversion of a Tartan 27, which we are very happy with. Ours has the Thunderstruck 8.5kw kit, which is now the 5kw kit, which is more accurate. i believe if you go to 72V that will may require stricter Coast Guard regulations, but I could be mistaken. Mine is 48V. We have about 3-4 hours of range using Trojan 8V, 190 amp batteries. You may find your range will be minimal using 75Amp batteries. A freind of mine did a conversion of a Bombay Clipper, I don't think a 31 though. He went with the Marine Propulsion kit, which was a very nice set-up. Good luck!
Fred LiesegangTartan 27-2 Eagle
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No.
No experience with panels specifically, but nothing that size will last while vibrating in the wind.
They are just too thin to last, without a substrate or backing of some kind.
I have no experience with flexible solar panels, but many of you do - what is your opinions/experiences: are flexible panels durable enough to be mounted by the eyelets only?
RegardsBendik, Norway
-- -hanermo (cnc designs)
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