I suppose it not possible to have a scan for overseas readers... Does it say anything about those strange Flyer/Panasonic batteries?
Recommend a bike for touring
- Thread starter VroomVroom
- Start date
Hmmm... nobody interested in a P2P exchange with some pdf of AktivRadfahren? 
(I'm jocking, I've only the article about the extraenergy test)
Thank you for the info Miles
(I'm jocking, I've only the article about the extraenergy test)Thank you for the info Miles
H2 Cells
Hydrogen cells are mentioned on the Swizzbee website here: swizzbee - I think the limiting factors at the moment though are price and where to fill up. I can see this technology taking off in the future however. Do you have any experience with this sort of fuel cell technology (I've only read about it so far)?
Firstly hello for a new member to this forum, it's good to see others concerned about the environment too
Hydrogen cells are mentioned on the Swizzbee website here: swizzbee - I think the limiting factors at the moment though are price and where to fill up. I can see this technology taking off in the future however. Do you have any experience with this sort of fuel cell technology (I've only read about it so far)?Gearing On A Torq
I've fitted my Torq with a 44 chain wheel: 13-32 cassette and an Alivio Rear mech. I think I've overdone it because as is reported, it will make no difference to the motor's gearing and the lowest speed where max torque lies. The hills are a devil with a Torq although my weieght must take some of the blame. Add some luggage and a spare battery and you may have to redesign the whole outfit. I'll be smiling when the battery goes flat out there in the boondocks.
I am deperately trying to find an electric bike where the motor drives the chain which drives a rear hub gear. The hills will disappear (I hope). I tried the Giant Twist but I could not keep up the pedalling rate required by the speed of the motor. The independent throttle was made for me - but the motor of the Torq was not made for those hills.
Itspeteinit
I've fitted my Torq with a 44 chain wheel: 13-32 cassette and an Alivio Rear mech. I think I've overdone it because as is reported, it will make no difference to the motor's gearing and the lowest speed where max torque lies. The hills are a devil with a Torq although my weieght must take some of the blame. Add some luggage and a spare battery and you may have to redesign the whole outfit. I'll be smiling when the battery goes flat out there in the boondocks.
I am deperately trying to find an electric bike where the motor drives the chain which drives a rear hub gear. The hills will disappear (I hope). I tried the Giant Twist but I could not keep up the pedalling rate required by the speed of the motor. The independent throttle was made for me - but the motor of the Torq was not made for those hills.
Itspeteinit
That right Itspeteinit. I'm always pointing out in this forum that it's a mistake to gear a Torq down for the rider. All that does is divide the available power, putting the rider's power out of synch with the motor, with the result that neither can win on it's own.
The Torq's high derailleur gearing is correct since it matches the motors gearing, and that's great for fast climbing moderate slopes, but no good for real hills, and especially with loads.
I don't understand what you've said about not being able to keep up with the Twist pedalling rate. For the Twist motor to work it's hardest, you slow down the pedalling rate. Pedalling faster reduces what the motor does, a mistake many make when they first try a Twist. If you get a chance to try one again, point it at a hill and this time slow down the pedalling and you'll find the motor takes up more of the work. To get the motor to do most of the work, you need to pedal really slowly. It's a trick I use all the time when pulling my large trailer. If necessary, you change up to get the cadence low enough, a very different technique from most cycling.
The Torq's high derailleur gearing is correct since it matches the motors gearing, and that's great for fast climbing moderate slopes, but no good for real hills, and especially with loads.
I don't understand what you've said about not being able to keep up with the Twist pedalling rate. For the Twist motor to work it's hardest, you slow down the pedalling rate. Pedalling faster reduces what the motor does, a mistake many make when they first try a Twist. If you get a chance to try one again, point it at a hill and this time slow down the pedalling and you'll find the motor takes up more of the work. To get the motor to do most of the work, you need to pedal really slowly. It's a trick I use all the time when pulling my large trailer. If necessary, you change up to get the cadence low enough, a very different technique from most cycling.
Torqs and Rider Gearing
Hi Flecc:
I guess you must be right (who am I to contradict you). But I can ask for an explanation of.......with regard to the Twist......
if there is no accelerator twist grip and the motor speed is governed by the Limiter, on the one hand, and all the other factors such a all-up weight, grade of the road (hill up) what tells the motor to go as fast as possible?
For that matter, what tells it to go at 10mph on the flat? if that is the desired speed.
By the way, seeing as 'ow your Quando does 22 mph (did I rememebr that right from you trip to the tip) in what way does it differ from the published spec and test report of the Quando I on 50 cycles web site, which incidently, says it has a single gear of 70 inches (48 / 14) x 20 ?
Peter
Hi Flecc:
I guess you must be right (who am I to contradict you). But I can ask for an explanation of.......with regard to the Twist......
if there is no accelerator twist grip and the motor speed is governed by the Limiter, on the one hand, and all the other factors such a all-up weight, grade of the road (hill up) what tells the motor to go as fast as possible?
For that matter, what tells it to go at 10mph on the flat? if that is the desired speed.
By the way, seeing as 'ow your Quando does 22 mph (did I rememebr that right from you trip to the tip) in what way does it differ from the published spec and test report of the Quando I on 50 cycles web site, which incidently, says it has a single gear of 70 inches (48 / 14) x 20 ?
Peter
You're misinterpreting the Quando writeup Peter. The over 26 mph was downhill, nothing to do with the motor capability, just gliding downhill as I wrote there. The maximum speed on an absolutely flat surface was the 17 mph, the 18 mph was on a minutely downhill bit (0.6%). I don't understand your reference to the Quando gearing. I also said it was 70", so I can't see the problem?
This one page on the 50cycles site reports the gearing of the Quando as 53", and I've twice asked for this to be corrected, to no avail so far. The prototype had a 54" gear because it used an 18 tooth freewheel, but the production bikes have the 14 tooth of course. Perhaps it was this you were thinking of that conflicted.
The Twist isn't so crude as to just use a limiter. The software adjusts the output according to the motor speed, which of course is directly linked to the pedalling speed as it's a pedelec which has to be pedalled. The software interprets a high pedalling speed as the rider not needing help and backs off the power to conserve charge. Conversely, it interprets a slowing down of pedalling as the rider struggling, so it then delivers more power. That's overridden by the pressure of your pedalling, which is what controls the speed. You pedal to 10 mph and stop pushing at that while still spinning the pedals, and it won't go faster. These relationships in the control are very complex as you can see, much different from the usual simple setups.
Therefore you can choose what you want by pedalling the right speed to tell it what to do, slow to get it to help more, fast to do the work yourself. That's how it works it's magic of a good range and performance, by optimising all the time, rather than crudely cutting in and out with a limiter.
In addition, to accord exactly with European law, the software gradually phases down the power from a pedal rate equal to 13.5 mph to a point where it ends at 15 mph, this overriding the other conditions.
Hope that clears things up for you.
This one page on the 50cycles site reports the gearing of the Quando as 53", and I've twice asked for this to be corrected, to no avail so far. The prototype had a 54" gear because it used an 18 tooth freewheel, but the production bikes have the 14 tooth of course. Perhaps it was this you were thinking of that conflicted.
The Twist isn't so crude as to just use a limiter. The software adjusts the output according to the motor speed, which of course is directly linked to the pedalling speed as it's a pedelec which has to be pedalled. The software interprets a high pedalling speed as the rider not needing help and backs off the power to conserve charge. Conversely, it interprets a slowing down of pedalling as the rider struggling, so it then delivers more power. That's overridden by the pressure of your pedalling, which is what controls the speed. You pedal to 10 mph and stop pushing at that while still spinning the pedals, and it won't go faster. These relationships in the control are very complex as you can see, much different from the usual simple setups.
Therefore you can choose what you want by pedalling the right speed to tell it what to do, slow to get it to help more, fast to do the work yourself. That's how it works it's magic of a good range and performance, by optimising all the time, rather than crudely cutting in and out with a limiter.
In addition, to accord exactly with European law, the software gradually phases down the power from a pedal rate equal to 13.5 mph to a point where it ends at 15 mph, this overriding the other conditions.
Hope that clears things up for you.
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I don’t now if this is the right place for my question, but… I was thinking about Flecc's modification of the SRAM 5 of the old Giant Twist, putting on a 17 tooth sprocket in place of the standard 19 tooth, which gives more speed but a little less hill climbing ability. I wonder if it would be possible to do this kind of thing in the other direction…
In next months it should be available the new S-series of the Biketech Flyer and I’m quite interested in it (even though the price will be outrageous, I suppose). Like the top of the T-series (and like the Swizzbee) it should have no speed restrictions, as permitted by the Swiss law (and also by the German law, if I understand correctly, which is important because Germany is part of the EU). In our countries such an unrestricted speed is not allowed and a better hill climbing ability would be a good thing for the Flyer.
So my question is the following. Changing the sprocket to a bigger one could make this kind of bicycles (Flyer S-series, Flyer T-series HS, Swizzbee) better hill climber and at the same time legal pedelec in EU countries?
In next months it should be available the new S-series of the Biketech Flyer and I’m quite interested in it (even though the price will be outrageous, I suppose). Like the top of the T-series (and like the Swizzbee) it should have no speed restrictions, as permitted by the Swiss law (and also by the German law, if I understand correctly, which is important because Germany is part of the EU). In our countries such an unrestricted speed is not allowed and a better hill climbing ability would be a good thing for the Flyer.
So my question is the following. Changing the sprocket to a bigger one could make this kind of bicycles (Flyer S-series, Flyer T-series HS, Swizzbee) better hill climber and at the same time legal pedelec in EU countries?
Yes definitely Leonardo. Changing to a larger sprocket is perfectly ok and improves the hill climbing ability considerably. Below are the comparisons for different rear sprockets on the Lafree Twist series with an SRAM P5. In each line there's the sprocket number of teeth, bottom gear inches, the top gear inches, and last the maximum assisted speed in the top gear:
19 tooth, 31", 77", 14.4 mph
20 tooth, 29", 73", 13.7 mph
21 tooth, 28", 70", 13.1 mph
22 tooth, 26", 67", 12.6 mph
Hope that's some help to you.
19 tooth, 31", 77", 14.4 mph
20 tooth, 29", 73", 13.7 mph
21 tooth, 28", 70", 13.1 mph
22 tooth, 26", 67", 12.6 mph
Hope that's some help to you.
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Thank you very much Flecc! I’m going to check your suggestion with the Italian dealer of the Biketech Flyer. I think it should be of their interest first of all.
Thanks flecc for the explanation of "How the Giant Twist controls motor speed".
Why do manufacturers think we are so dim (probably right in my case) that we can't understand the technology applicable to riding, so they don't bother to publish it on the Selling Blurb. There has been much said about understanding how Motor Cars work (Clutch, Brakes, Gear Levers, etc) which improves driving ability.
I made a complete hash of my remarks about the Quando: I did it late at night- not a good time. Of course 50 Cycles site says the gearing is 53 inches - so they have not changed it.
Peter
Why do manufacturers think we are so dim (probably right in my case) that we can't understand the technology applicable to riding, so they don't bother to publish it on the Selling Blurb. There has been much said about understanding how Motor Cars work (Clutch, Brakes, Gear Levers, etc) which improves driving ability.
I made a complete hash of my remarks about the Quando: I did it late at night- not a good time. Of course 50 Cycles site says the gearing is 53 inches - so they have not changed it.
Peter
You're right Peter, I also get irritated at manufacturers who assume we won't understand, as I look in vain for essential technical information.
I'm sure the problem is that they pander to those who can't cope with technology, sadly at least 70% of the population, and don't want to frighten them off a product with complications. No excuse though, all they have to do is provide two levels of specification information, one shown as advanced. As the saying goes, it's not rocket science!
I'm sure the problem is that they pander to those who can't cope with technology, sadly at least 70% of the population, and don't want to frighten them off a product with complications. No excuse though, all they have to do is provide two levels of specification information, one shown as advanced. As the saying goes, it's not rocket science!
Hello... my first post here, very interesting forum !
i have read 1 page early the concerns about LiIon, the Danger, burned houses, ...
and want to say some thing about that..
iam using LiPos (Kokam, Thunderpower, Tanic, Polyquest, Xcell, ...) for some years now in RC-planes, RC-cars and RC-helis
also using LiIon cells (Mangan-basis)
and the ne FePO4-cells
for burning down your house: this can only happen in the badest circumstances with LiPos and some Cheap cobalt-based LiIonbs
it will for example not happen with Konion or FePO4 !
(or at least: it is as unusual as that it will happen with Nicd or NiMh --> in reality: a Konion will shut down when it reaches 90°C.. a NiMh or NiCd on the otherhand will heat up MUCH more and can cause a fire..)
so.. said that..
---------------------------------------------------
for life-time:
in RC-heli-Use (heavy use) we see around 100-150cycles with the good LiPos
shelflife: 2-3 years (after that time, unimportant if used or not the batts are dead without any power)
Konions: 300cycles (a friend has already 700cycles at use with moderate currents with these cells) - lifetime.. lets estimate 5 years
FePO4: at moderate use said to reach 1000-5000cycles, lifetime is said by a tech-engineer from A123systems: 10years !
----------------------------------------------------
what kind of power can you get with this cells ?!?
well: the problem is: at a bike you need a lot of Ah to carry with you
a lot of Ah cost a lot of money ==> for that cheap cells are used !
for safety reason and easy use, best thing for Bikes in my opinion would be
Konion or FePo4
so, what can a Konion do ?
the new Konion 1300 costs 12Euro each cell, good cell
the "old" Konion 1100 can be got for 3,5-4euro each cell when you disassamble a 36V battery-pack from BOSCH-tools
for a bike i would want a 36Volt pack with 10Ah...
with Konion 1100cells you would need 90 cells
that would cost around: 350Euro
would it be strong enough for an e-bike ?
i think so:
it would handle 108A continouse (providing 31,8Volt average) => 3400Watt continously
and 200A for 10seconds PEAK (providing 29Volt average) => 5800Watt short
you see: power of the batterie is absolut no argument anymore, that a e-bike has not enoug power or cycle-life of batts is low..
weight of the pack: 3,8-3,9kg
with this above shown numbers you can expect 200-300cycles with that batteries (i get that amout in my Heli stressing the batts that way)
so, what can a FePo4 battery do ?
one single cell is available for 10 Euro (dismounting a DEWALT-tools battery)
2300mAh each cell, around 3Volt under load
i would use for a bike:
12cells in series paralleled by 4,
so: 48cells
price: around 480euro
capacity: 9,2Ah
Power ?
continous power: 31Volt * 240A = 7400Watt
short power: 29Volt * 400A = 11600Watt
weight: 3,6-3,7kg
you see: these are values you will not see with an bike..
the batteries are stressed A LOT LESS in a bike..
for the Fepo4-pack
when using continously 3500Watt out of such a battery-pack (which is still much more a bike will need)
and charging the battery not faster than 15min (YES, the batteries are cabable to be charged to 95% full within 5min !!! (if you find a strong enough charger *lol*)
the manufactor guarantees more than 1000cycles !!!
and lifetime of 10years ! after that, capacity would be down to 80%
so..
to show some real-world data,
here a graph i logged last weekend in my E-Heli...
think about: only 4 cells were used !!!
battery-weight: only 280g !
still peaks in the 900Watt Region !
Average were 250Watt (out of this 280g battery !)
after the flight the batts were around 40°C hot (they are allowed to reach 60°C-70°C by the manufactor)
and recharged with 8A-charger within 16min !
here the graphs:
what i wanted to show you:
there are already VERY GREAT batteries out there !
IF you are willing to take a solder-iron and make your own packs..
nearly 100% of the cells sold on the bike-market are already "old technology" (2years old), weak cells, with relativly short lifetime...
oh: just another example what is possible with NEW generation, high-power Lipos:
the pack on the pic can give up to 55.000Watt !!!! of power ! (the motor can not handle that much, and of course it would result in too short runtime.. but the batts can handle it !)
i have read 1 page early the concerns about LiIon, the Danger, burned houses, ...
and want to say some thing about that..
iam using LiPos (Kokam, Thunderpower, Tanic, Polyquest, Xcell, ...) for some years now in RC-planes, RC-cars and RC-helis
also using LiIon cells (Mangan-basis)
and the ne FePO4-cells
for burning down your house: this can only happen in the badest circumstances with LiPos and some Cheap cobalt-based LiIonbs
it will for example not happen with Konion or FePO4 !
(or at least: it is as unusual as that it will happen with Nicd or NiMh --> in reality: a Konion will shut down when it reaches 90°C.. a NiMh or NiCd on the otherhand will heat up MUCH more and can cause a fire..)
so.. said that..
---------------------------------------------------
for life-time:
in RC-heli-Use (heavy use) we see around 100-150cycles with the good LiPos
shelflife: 2-3 years (after that time, unimportant if used or not the batts are dead without any power)
Konions: 300cycles (a friend has already 700cycles at use with moderate currents with these cells) - lifetime.. lets estimate 5 years
FePO4: at moderate use said to reach 1000-5000cycles, lifetime is said by a tech-engineer from A123systems: 10years !
----------------------------------------------------
what kind of power can you get with this cells ?!?
well: the problem is: at a bike you need a lot of Ah to carry with you
a lot of Ah cost a lot of money ==> for that cheap cells are used !
for safety reason and easy use, best thing for Bikes in my opinion would be
Konion or FePo4
so, what can a Konion do ?
the new Konion 1300 costs 12Euro each cell, good cell
the "old" Konion 1100 can be got for 3,5-4euro each cell when you disassamble a 36V battery-pack from BOSCH-tools
for a bike i would want a 36Volt pack with 10Ah...
with Konion 1100cells you would need 90 cells
that would cost around: 350Euro
would it be strong enough for an e-bike ?
i think so:
it would handle 108A continouse (providing 31,8Volt average) => 3400Watt continously
and 200A for 10seconds PEAK (providing 29Volt average) => 5800Watt short
you see: power of the batterie is absolut no argument anymore, that a e-bike has not enoug power or cycle-life of batts is low..
weight of the pack: 3,8-3,9kg
with this above shown numbers you can expect 200-300cycles with that batteries (i get that amout in my Heli stressing the batts that way)
so, what can a FePo4 battery do ?
one single cell is available for 10 Euro (dismounting a DEWALT-tools battery)
2300mAh each cell, around 3Volt under load
i would use for a bike:
12cells in series paralleled by 4,
so: 48cells
price: around 480euro
capacity: 9,2Ah
Power ?
continous power: 31Volt * 240A = 7400Watt
short power: 29Volt * 400A = 11600Watt
weight: 3,6-3,7kg
you see: these are values you will not see with an bike..
the batteries are stressed A LOT LESS in a bike..
for the Fepo4-pack
when using continously 3500Watt out of such a battery-pack (which is still much more a bike will need)
and charging the battery not faster than 15min (YES, the batteries are cabable to be charged to 95% full within 5min !!! (if you find a strong enough charger *lol*)
the manufactor guarantees more than 1000cycles !!!
and lifetime of 10years ! after that, capacity would be down to 80%
so..
to show some real-world data,
here a graph i logged last weekend in my E-Heli...
think about: only 4 cells were used !!!
battery-weight: only 280g !
still peaks in the 900Watt Region !
Average were 250Watt (out of this 280g battery !)
after the flight the batts were around 40°C hot (they are allowed to reach 60°C-70°C by the manufactor)
and recharged with 8A-charger within 16min !
here the graphs:
what i wanted to show you:
there are already VERY GREAT batteries out there !
IF you are willing to take a solder-iron and make your own packs..
nearly 100% of the cells sold on the bike-market are already "old technology" (2years old), weak cells, with relativly short lifetime...
oh: just another example what is possible with NEW generation, high-power Lipos:
the pack on the pic can give up to 55.000Watt !!!! of power ! (the motor can not handle that much, and of course it would result in too short runtime.. but the batts can handle it !)
Welcome to the forum kraeuterbutter, and thanks for a very interesting first post.
You paint a tantalising picture of those batteries lives and technical performance, and I wonder why it is that manufacturers are not already using them.
I know that some electric bike firms have been looking at many alternatives and carrying out in depth trials, but have often been disappointed with the real world performance of what seemed promising types.
Have you an opinion on why it is that the manufacturers aren't adopting these types that you are so satisfied with? The only thing I can see that they might object to is batteries in series/parallel formations, though I appreciate that isn't a problem with many lithium based types now.
.
You paint a tantalising picture of those batteries lives and technical performance, and I wonder why it is that manufacturers are not already using them.
I know that some electric bike firms have been looking at many alternatives and carrying out in depth trials, but have often been disappointed with the real world performance of what seemed promising types.
Have you an opinion on why it is that the manufacturers aren't adopting these types that you are so satisfied with? The only thing I can see that they might object to is batteries in series/parallel formations, though I appreciate that isn't a problem with many lithium based types now.
.
hi..
(please excuse my bad english, iam German speaking (from Austria))
hmm.. maybe there are more than one reasons:
first i should introduce, what C-rating is to understand my following post better:
C-rating does say, how much current you can draw out of a battery..
example:
a battery with 15Ah and 1C Rating --> can deliver 15A continously without getting too hot or damaged
a battery with 15Ah and 2C Rating --> 2 * 15A = 30A
15Ah and 3C Rating --> 3 * 15A = 45A
on this rating you see, that LeadAcid-batteries often have only a 2C continous rating in reality... (a 10Ah batterie should not be used with more than 20A continously)
1.) price ?!?
because of cheaper price for bike-batteries often 1C-2C-batteries are used
using more A than 2C will damage the battery or shorten the life
on rc-planes we use nowadays 20C batteries..
so: a 3,2Ah Kokam battery can provide 60A continously (peaks up to 100A)
unfortunatley this cells are more expensive as well :-(
i see it often on rc-flying too: people get cheap LiIon from ebay, which were designed for laptops and co... (1C or 2C cells)
much too week for rc-flying ==> 30 cycles and the batts are dead
more expensive KONION cells (10C cells) on the otherhand will hold 250-300cycles in same application
so on long run much cheaper
2.) on a bike you don´t need high-power-cells
more important is maybe most capacity for weight
a high power 20C Lipo cell weights about 20% more than a 5C Lipo cell..
3.) we at rc-flying use often small (=cheaper) batteries..
so we can afford to buy every some weeks/month new batts that come to the market.. and test them.. and find out the good things/bad things about it
for a e-bike i would also not afford every 3-4 month 500 Euro for a new battery
so the market is FAR not that fast changing like on rc-flying
to get you a little impression of what is possible:
here a video of a RC-heli with a 1250g light battery
it is a "soft" setup (only 10cells) with around 2500-2800Watt peaks
power-junkies fly the same heli with 15cells and than 4000Watt peaks !
the battery used has 37Volt and 4,9Ah
the rotor of the heli has a size of 1.6meters (so: a deadly weapon )
VIDEO Acrobat SHARK
the batterie on that last for about 150cycles, maybe 200cycles
and for last:
here again a diagramm for comparing cells:
NiMH vs. Lipo
left the lipos, right the NiMh
the lipos on the left side are already 2 years old, OLD technologie -> only 13C-cells !!
nowadays we use 20C-25C cells, and next month kokam releases a new 30C cell..
so 2,5times the power at same weight than my Lipo-pack on the diagramm (also my old lipo-pack is already supperior compared to the NIMh)
the NiMh on the right side is realy week...
Lipo on the left: 342g
NiMh on the right side: 440g
here the same diagramm for power:
i know e-bike users who changed from acid to NiMH and think that NiMh are "the best"
well: the diagramm above shows, how a NiMh (and i payed 80 Euro for that one !) compares to a 2 year old (= old technologie) Lipo (130 Euro)
for using cells in parallel:
the Konion cells for example:
after 75cycles a test has shown, that the cells within the pack are drifting only by 0,004 Volt maximum !
thats less than 0,1% !!!
so there is absolut NO problem paralleling this cells !
(Bosch for example sells there power-tool-packs with paralleled cells inside !)
conclusion:
i think it will last 2-3 years until this good cells will become available for e-bikes too...
(i see it in the rc-market: we are flying already for 3-4years with Lipos... the Rc-boats have started 1-2 years ago, and rc-cars are starting this year.....
and on e-bikes market is MUCH slower)
(please excuse my bad english, iam German speaking (from Austria))
hmm.. maybe there are more than one reasons:
first i should introduce, what C-rating is to understand my following post better:
C-rating does say, how much current you can draw out of a battery..
example:
a battery with 15Ah and 1C Rating --> can deliver 15A continously without getting too hot or damaged
a battery with 15Ah and 2C Rating --> 2 * 15A = 30A
15Ah and 3C Rating --> 3 * 15A = 45A
on this rating you see, that LeadAcid-batteries often have only a 2C continous rating in reality... (a 10Ah batterie should not be used with more than 20A continously)
1.) price ?!?
because of cheaper price for bike-batteries often 1C-2C-batteries are used
using more A than 2C will damage the battery or shorten the life
on rc-planes we use nowadays 20C batteries..
so: a 3,2Ah Kokam battery can provide 60A continously (peaks up to 100A)
unfortunatley this cells are more expensive as well :-(
i see it often on rc-flying too: people get cheap LiIon from ebay, which were designed for laptops and co... (1C or 2C cells)
much too week for rc-flying ==> 30 cycles and the batts are dead
more expensive KONION cells (10C cells) on the otherhand will hold 250-300cycles in same application
so on long run much cheaper
2.) on a bike you don´t need high-power-cells
more important is maybe most capacity for weight
a high power 20C Lipo cell weights about 20% more than a 5C Lipo cell..
3.) we at rc-flying use often small (=cheaper) batteries..
so we can afford to buy every some weeks/month new batts that come to the market.. and test them.. and find out the good things/bad things about it
for a e-bike i would also not afford every 3-4 month 500 Euro for a new battery
so the market is FAR not that fast changing like on rc-flying
to get you a little impression of what is possible:
here a video of a RC-heli with a 1250g light battery
it is a "soft" setup (only 10cells) with around 2500-2800Watt peaks
power-junkies fly the same heli with 15cells and than 4000Watt peaks !
the battery used has 37Volt and 4,9Ah
the rotor of the heli has a size of 1.6meters (so: a deadly weapon
)VIDEO Acrobat SHARK
the batterie on that last for about 150cycles, maybe 200cycles
and for last:
here again a diagramm for comparing cells:
NiMH vs. Lipo
left the lipos, right the NiMh
the lipos on the left side are already 2 years old, OLD technologie -> only 13C-cells !!
nowadays we use 20C-25C cells, and next month kokam releases a new 30C cell..
so 2,5times the power at same weight than my Lipo-pack on the diagramm (also my old lipo-pack is already supperior compared to the NIMh)
the NiMh on the right side is realy week...
Lipo on the left: 342g
NiMh on the right side: 440g
here the same diagramm for power:
i know e-bike users who changed from acid to NiMH and think that NiMh are "the best"
well: the diagramm above shows, how a NiMh (and i payed 80 Euro for that one !) compares to a 2 year old (= old technologie) Lipo (130 Euro)
for using cells in parallel:
the Konion cells for example:
after 75cycles a test has shown, that the cells within the pack are drifting only by 0,004 Volt maximum !
thats less than 0,1% !!!
so there is absolut NO problem paralleling this cells !
(Bosch for example sells there power-tool-packs with paralleled cells inside !)
conclusion:
i think it will last 2-3 years until this good cells will become available for e-bikes too...
(i see it in the rc-market: we are flying already for 3-4years with Lipos... the Rc-boats have started 1-2 years ago, and rc-cars are starting this year.....
and on e-bikes market is MUCH slower)
oh..
the next step:
Electric Moto Corporation - great picture with details
18hp !
http://www.electricross.com/
and this:
14.400Watt = 19hp
: : Electric Moto Corporation - Blade Specifications : :
the bike weights only 36kg !
the battery (LiIOn FePo4) weights only 13kg
so: maybe 2 times the weight of some e-bikes
but 20 times the power
(the 13kg light LiIon can handle that)
there are also videos on the pages
the next step:
Electric Moto Corporation - great picture with details
18hp !
http://www.electricross.com/
and this:
14.400Watt = 19hp
: : Electric Moto Corporation - Blade Specifications : :
the bike weights only 36kg !
the battery (LiIOn FePo4) weights only 13kg
so: maybe 2 times the weight of some e-bikes
but 20 times the power
(the 13kg light LiIon can handle that)
there are also videos on the pages
Thank you again kraeuterbutter. That fits well with my understanding, and I agree that it will probably be two to three years before we get the newer types.
At present, I find NiMh are still often best in practice on electric bikes, simply because the Lithium types often drop voltage so much that the cut-out operates when under high current drain conditions. In that respect NiMh are superior at present since the voltage drop is so much less.
I would rather reach the top of a hill with a technically inferior battery than fail half way up with a technically better design!
Hopefully there may be much better things to look forward to in our bikes.
The video is very good in every way. Stunning flying control and excellent camera work, especially the skill of keeping the helicopter centre screen. If only our full size helicopters could have this incredible agility. Perhaps the passengers wouldn't survive though!
.
At present, I find NiMh are still often best in practice on electric bikes, simply because the Lithium types often drop voltage so much that the cut-out operates when under high current drain conditions. In that respect NiMh are superior at present since the voltage drop is so much less.
I would rather reach the top of a hill with a technically inferior battery than fail half way up with a technically better design!
Hopefully there may be much better things to look forward to in our bikes.
The video is very good in every way. Stunning flying control and excellent camera work, especially the skill of keeping the helicopter centre screen. If only our full size helicopters could have this incredible agility. Perhaps the passengers wouldn't survive though!
.
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