Batteries and New Battery Technologies

" land of espousing free speech has it enshrined in their constitution but often denies it to others" You don't get it yet - Do realize you just got your off-topic jab in and you did the same thing I did (but colored by another belief system)? Also, there is nothing in my Constitution about you. There is nothing in my Constitution that says "arrogant liberal from down under gets the last word." Dang, Mas, since you seem to know a little about this place, you should know that "freedom of speech" is a legal concept and nothing to do with any forum - just that Americans can say what we want and not get shot for it. You have every right to ask me to talk on your thread instead of this one but I really have no desire to butt heads with people - I'd like to stick on topic. Your fingers can't type "post 176"? All that said, I'll leave this thread alone for a day or two, and as long as it hasn't devolved again, I won't either.

 

Speed

Pleased to be back at the right topic
That was two mighty interesting movieclips. The speed seems to be very acceptable. Thanks for the small motor website. I have always been battling in obtaining those small motors. I do get them also from the hobbyshop, but at a price premium.
What is your thought on using 24 Volt automotive truck motors and put 2 motors in serie on 48 Volt. There maybe small differences, but that could one easy compensate. The cost of those motors on the scrapyard are minimal.
Bert

 

BertKu, are you talking starter motors? - far to heavy on amperage and only designed for brief bursts to start the engine - would kill a battery very quickly (not just flatten it) - actually kill it as a battery.....

 

After seeing these little PMSM I would never bother using brushed motors. The PMSMs are 3-Phase and cannot be run in series because you cannot get to the star point. Also they operate at synchronous speed so if the motors had unballanced loads the controller would be confused.

The motors are tremendously powerful for their size. In fact the most powerful I have seen for the model plane stuff is rated at 6kW and is two smaller motors on a common shaft. You can gang two motors like this because they will have locked bodies on a common shaft and will be synchronised. You cannot gang more than two because the bodies spin - not the shaft.
http://www.hobbycity.com/hobbycity/...ame=AXi_5330-Double_GOLD_LINE_Brushless_Motor

Hobbycity is a good firm to deal with. Good prices and fast delivery. I have had 4 or 5 orders from them now.

Rick W

 

Hi Masalai, No I was more thinking on other motors used in large trucks, like single windscreen wiper motors or windows motors. But Rick W has answered my question and I will consider also to try the 3 phase motors out. But I just got back from overseas after some sailing on the Kaager plassen in Holland and cruising on a luxury cruize liner from Barcelona and I am a little cash stripped. The Hollanders have developed their electric hybrid systems quite nicely and are using either dry lead sealed batteries or NiHM (very expensive). I was watching those 6 meter yachts running on batteries and electric motors. Very silent and smooth.
Bert

I forgot. I spoke to a skipper and he was using Royal deep cycle Calcium batteries. Each 12 Volt - 200 Amperhour and seem to be quite happy with them. Anybody else who has experience?

 

Gentlemen, feet back on the ground please, it is not all gold out there.
These wonderful powerful motors do have impressive specs but to use such a motor for the propulsion of a boat or other vehicle is quite something else:

-Current consumption is given as xx Amps/ yy seconds, in other words "burst mode". No duty cycle is mentioned; I wouldn't be surprised if that turns out to be 5% or less. What you need for real life applications is continuous duty. That will require a considerable airstream through the motor.

-The efficiency may peak above 90% but the useful power range is given for the 85% points. Assuming the controller does equally well, 100 Watts electrical input gives 72 Watts mechanical output, minus 4 Watts for a blower makes 68 Watts. Not exactly spectacular.

-No data about design life or MTBF (mean time between failures). To get an MTBF of 2000 hours you need conservatively rated bearings and little thermal stress. I bet these guys designed for high performance only.

-These little buggers are expensive! Mass produced electric motors like the automotive ones cost only a fraction and perform very reasonably.

The outrunner design originated in Germany in the 60's: the Papst Aussenlaufer. By putting the coils within the rotating magnet shell the air gap is further from the shaft center, so there is more torque. Papst was so kind to add vanes to the bottom of the drum, so there was cooling provided.

 

The little motors are good to play with to learn about the technology.

The Mars motor is a step above. Still not industrial but certainly in the commercial arena.

Have you ever looked at how much running a typical outboard does. My bet is that there are not many that have actually done 1000 hours. I have no experience with the modern 4-stroke but back in the 70s if you got 400 hours of hard use before the first rebore you were lucky.

The electric approach requires a whole design approach. You are not going to build a realistic electric boat to plane with the current state of batteries. You can get one to plane but it will last maybe 30 minutes before recharging.

Electric is fine for sailing. I had an 8HP diesel in a 3t yacht that usually ran at 4HP or there abouts based on the fuel consumption. Would do 6kts. In 4 years of regular use I clocked up 80 hours on said motor. It was use to get on and off the mooring and now and then when the wind dropped and I needed to be somewhere else. So not what I would call hard use.

For electric powered vessel you have to take a different tack and this is getting to be possible with good hydrodynamic design and modern lightweight materials.

The linked rendering is for a 9.5m boat. It is intended for limited coastal cruising. It has spartan accommodation and will be built light. It will have a large prop so it operates efficiently and have the bollard pull of a much more powerful motor. It requires 750W at the motor to do 8kts. 4.5kW will get it to 15kts. Motor and controller have a combined efficiency of 88% at the selected rpm and power. Normal operation will be well within the motor rating. Motor will be mounted in the cabin out of the worst of the weather.
http://www.boatdesign.net/forums/at...-skinny-power-boats-sw_tri_9-5m_linesplan.jpg

The 3 solar panels will produce 675W in good sunlight and it will have a 1kW wind generator rated at 10m/s - only 6m/s when boat is going to windward at design speed. Intended batteries are 4kWh of lithium.

I am still in the proof of concept phase but nothing looks impossible with the idea. Range will be limited by my provisioning only but intention is to coastal hop. If I get 1000 hours use a year out of it then it will be used more than I expect. (Many people are thinking about replacing a car after 4 years - probably less than 1500 hours operation.)

If you scale up something like this you can start to build in accepted comforts that I am happy to live without. Costs go up accordingly.

Rick W

 

Solar/wind/electric boat

Hi Rick W. That is excactly what I was looking for. Are there patent rights on producing a similar boat? The beam is 2,25 meters by 9,5 meter. The solar panel areia is 1.09 m2 at 16 % efficiency sunlight gives 175 watt of energy.
3 panesl = 525 watt.
Excellent, concept. If the boot uses 2000 watt of electric motor power you will get quite a distance before the battery is pap. If you over and above have some wind, you don't even have to stop at all. I am more in favor for a sturdy Calcium battery for the time being. The battery you have selected is a ******* to re-charge all the time ciorrectly.
All what I need is to find a good electric motor. Thanks Rick, However we have here at the coast normal waves of 1,5 to 2 meter. With a little bit of wind 2,5 - 3 meter and with a light storm 5 - 6 meters. Not to speak of a decent storm at 10 meter waves. What is your expectation in weather conditions as above prescribed.???
Australia is also not as easy when it comes to waves. What is your forecast to use this type of boat on your seas?

I need to speak to a local boatbuilder to give me some ideas on how to construct the inside.

Are you willing to give more secrets away?
Bert

 

Bert
There are no secrets. It is all in development. The boat has to be built very light. I have not gone through the detail design process for the construction but the aim is a hull around 250kg and this will only be achieved with carbon fibre. It seems ridiculously low for a 9.5m hull but when look at modern ocean racing cats and consider the loads they handle then you realise my target is not unrealistic.

The lithium batteries have very good energy density and the Mars motor weighs 10kg.

The hull is just over 2m wide but the initial stability is very good because it is really a trimaran. Its stability matches a much wider monohull while still retaining the ability to be self righting. The batteries in the bottom of the central hull act like a ballasted keel.

My power estimates have proven to be very reliable because I have some very good design tools that I have found over the last few years. I have been building pedal boats as test platforms to prove design ideas. My V11 hull design is the current 24 hour distant holder for human power 245km. This is a clip of V11J in action at 6.5kts:
http://www.youtube.com/watch?v=8BiGp94RLX0
It takes 150W to hold this speed.

The solar boat is just a longer, heavier version of this with a cabin on top. It will weigh 4 to 5 times more and require about 3 times the power to do the same speed or 750W to get to 8kts.

The faux-tri idea is the most energy efficient hull form I have seen to date. It does not surprise me that the latest military craft are using this configuration.

The little Turnigy PMSM I have will be used to power a 1/5th scale model of the proposed boat just to get a feel for the cabin design and handling characteristics.

Rick W

 

BertKu,
Never heard of "calcium" batteries - looked at some reports on 'cold' sodium but quite risky in a water environment but could be efficient and light - no thanks - - yet... The spiral wound are lead/acid types known as AGM or "absorbed glass matt" - heavy, can hold a fair charge and should be recharged before 40 to 50% discharge.... The Torqeedo electric 'outboard' motors are fairly efficient OVERALL - power used and converted to effective thrust, and will suit my 4,500kg loaded, sailing cat, pushing it in still water at up to 6 knots with 2 units rated at 4000w on 48VDC peak each (2000w cruise, I would expect around 4knots)

 

Hi Rick, I am not that lucky that I can afford to build it from Carbon Fibre. I may have to build it from light plywood. It means that in the years to come maybe I am rewarded and will get lighter more powerfull HiHM battereis and I may have do it with a lower speed for the time being. The Calcium batteries are here R 2809 each ( US$ 350) and weigh 55.7 Kg for a 200 Amperehour. 4 off them is 225 kg, quite a weight and it will slow it down, special in some waves.

You have already put quite some work and time into your design.
Bert

 

Hi Masalai, I haven't mastered yet on how to add a photo to a reply. The manufacturer is Delkor. They have some 20 different models and sells them as "Royal Deep Cycle and Royal Marine" series. 12 Volt
Bert

 

Aplogy

Hi CDK, I have apologised in 187 - One has to be carefull to make a joke, as it can sometimes come across as rude.
Bert

 

I sold my last yacht 17 years ago when my children were into sports that did not include sailing. I got heavily involved in their sports for about 10 years. They have now got through all that and I started thinking about a new yacht 7 years ago but it was going to be something different. I played with a few ideas at small model then decided to build something bigger when I had a long break from work.

The pedal boats provided a great interest and are real fun. I race mine against kayaks and canoes on an annual marathon race over 404km and do quite well. I get classed with unrestricted boats such as surf skis and am competitive even though I am not as fit as the guys who just do it for fitness in contrast to my engineering interest.

They have given me the platform to experiment with hull design and I have tried most forms of hulls and propulsion systems. I now have very accurate design tools for boats.

I realised a year or two ago that a propeller driven boat would suit my needs better than a conventional sailing boat. I have been asked on occasions to join in in sailing races at the local lake with my pedal boats but I can beat th entire fleet unless it is very windy and then the bigger cats can beat me. It is quite fascinating to be able to go directly upwind. I always gain on upwind legs even against the cats.

The first full-scale boat idea was a 12m long boat that could be split into parts for transport but its accommodation was poor. Then one of the forum members suggested the tri idea and I worked through it and it came out very well.

I have quite a few ideas that lead to more efficient boat overall. None are novel but I have engineered them so they work and in combination they provide outstanding efficiency.

My props are completely different to any normal boat prop. They get efficiencies in the mid to high 80s compared with 60 to 70% for most outboard props. I have very low drag appendages.

There is lots of information on this thread:
http://www.boatdesign.net/forums/boat-design/pedal-powered-boats-23345-20.html

One of my designs is currently being built for an ocean crossing under pedal power. It will outperform ocean rowing boats by a good margin:
http://www.adventuresofgreg.com/HPB/uploaded_images/P5270066-757314.JPG
It is an 8m long boat that has a hull weight of 55kgs. All carbon fibre on Corecell foam. Very strong and light - but expensive for weight.

Building heavier means you need to compromise on speed. My objective has been a cruise speed of 8kts so I can do decent coastal hops between ports.

If you want to have some fun on the water you can build a nice pedal boat for a few hundred dollars. It is quite surprising how much distance you can cover. I normally do 20km in a couple of hours on a Saturday or Sunday morning. Just go round and round the lake most of the time but I enjoy it more than playing golf or riding a bike. Sometimes I will go for a drive to a new lake or river and explore.

Rick W