No cogging or with cogging, hmm

bike4life

Active Member
Joined
Mar 19, 2018
Messages
372
You were right actually. It was well worth checking out the Hobby King packs made for remote control devices, "drones" and r/c cars and helicopters etc. The 44,4v nominal that you get when running four of their 11.1v in series is not less real world voltage than a 48v Li-ion battery on most Ebikes, because of the high "C rating" these packs don't suffer from voltage sag when heavily loaded. On my little "250w" overvolted and 333w continuous the peak watt usage would be only barely into the figures where the high Court rating makes a big difference. On the popular 1-3kw motors that are popular in the USA the lithium polymer packs have significant advantages.
The rate of voltage drop as you use up the usable voltage of the battery is different too. The Li-poly has a higher voltage when it is "empty" so actually it's average voltage is about the same as the Li-ion which begins with a higher voltage and ends with lower.

But then there are some other considerations. If you are a beginner and you read the posts about living with these batteries it does come across that everyone is getting through multiple chargers and power supplies before they find one that lasts a while, but not forever. There seems to be no charging system that is guaranteed to work for everyone all the time. Even if you make a list of the choices that other builders finally settled on, there's someone else saying that didn't work for them. There's no consistency, no consensus to follow so you can just buy once and have reliability.
They recharge quickly but..
The batteries and chargers and power supplies should be placed in a fireplace during the charge process and must be monitored.
You have to carry a pair of server power supplies and a very large charger and the battery medic etc if you are going on a road trip. Not like the compact little chargers used for the common Li-ion "ebike" batteries.
So for me, for touring and fishing expeditions, I don't think that Li-poly is a practicable option. I need to be able to carry a small charger or two in my panniers, with a campsite electric hook up (or whatever you call them there, RV mains plug and cable), and charge my battery inside my highly flammable tent whole I sleep or on my gasoline loaded bicycle.

But I'm glad I had a look at these. They do look nice and compact and good for high power "sport" ebiking near to home.
I wonder if your thing about the front wheel locking up from the regen in a big concern. I think a lot of other ppl do it and i havent heard that much about this issue. I believe you dont need to worry about backcurrent because there are stud diodes in the controller to prevent any backflow i think. What u need to worry about is i just found out that buying off alibaba is a pita. I was looking at shipping costs and see u have to find a shipping company and get quotes and the lowest i could find was $400 to ship this $100 ebike kit to the USA from jinsuang china. And by boat it was like $1000 because off tarriffs and import fees and customs bonds and all this sh*t. like wtf y so much money!!!! See Alibaba only works if u are buying enough to fill a shipping container. I was thinking abut mass producing these bikes in scale as a side job and now i am a little upset b/c amazon prices are a lot higher and i know that by running it through the rear wheel, thats extra time and sometimes the gear shifter and the gear cassettes don't work perfectly ie a 6speed cassette and 7 speed shifter could make a disaster if you put it in 7 at x speed.
But good luck with your build. The only real issues i think of like the ppl who buy a 3000w cyclone kit and have a 48v 20ah battery. The battery can only provide 1000w peak so u are only getting 1/3 of the motors potential or 1/3 the top speed.
 


Street Ryderz

Well-Known Member
Joined
Oct 14, 2016
Messages
2,951
You were right actually. It was well worth checking out the Hobby King packs made for remote control devices, "drones" and r/c cars and helicopters etc. The 44,4v nominal that you get when running four of their 11.1v in series is not less real world voltage than a 48v Li-ion battery on most Ebikes, because of the high "C rating" these packs don't suffer from voltage sag when heavily loaded. On my little "250w" overvolted and 333w continuous the peak watt usage would be only barely into the figures where the high Court rating makes a big difference. On the popular 1-3kw motors that are popular in the USA the lithium polymer packs have significant advantages.
The rate of voltage drop as you use up the usable voltage of the battery is different too. The Li-poly has a higher voltage when it is "empty" so actually it's average voltage is about the same as the Li-ion which begins with a higher voltage and ends with lower.

But then there are some other considerations. If you are a beginner and you read the posts about living with these batteries it does come across that everyone is getting through multiple chargers and power supplies before they find one that lasts a while, but not forever. There seems to be no charging system that is guaranteed to work for everyone all the time. Even if you make a list of the choices that other builders finally settled on, there's someone else saying that didn't work for them. There's no consistency, no consensus to follow so you can just buy once and have reliability.
They recharge quickly but..
The batteries and chargers and power supplies should be placed in a fireplace during the charge process and must be monitored.
You have to carry a pair of server power supplies and a very large charger and the battery medic etc if you are going on a road trip. Not like the compact little chargers used for the common Li-ion "ebike" batteries.
So for me, for touring and fishing expeditions, I don't think that Li-poly is a practicable option. I need to be able to carry a small charger or two in my panniers, with a campsite electric hook up (or whatever you call them there, RV mains plug and cable), and charge my battery inside my highly flammable tent whole I sleep or on my gasoline loaded bicycle.

But I'm glad I had a look at these. They do look nice and compact and good for high power "sport" ebiking near to home.
I agree charging is their biggest down side,Like anything some users will have their issues,I've had r/c balence chargers for decades now and they last and work well for me.The hyperion system I'm currently using is just over 10 y/o and it runs of a 750 w computer power supply that I just bridged everything to out put terminals added to the case with a switch cost me like 35 bucks the charger was like almost $300 but it can charge 2 6cell packs at once at up to 10a out put for each.Batteries when it come to rechargeable chemistry's have allways was been sketchy,when we used ni-cad prior to the lithium chemistrys they blew up,caught fire and stuff as well when misused yet I've never even poped a cell.I like the li-po for weight, size and power,price is not bad because there is no bms in the pack,you can use a bms to be able to use a simple charger but in most cases it's the bms that holds back amp levels so I dont use them LOL.There are lot's of ways to go it's fun learning,playing with the electric's with deep pocket's I believe the sky is the limit!
 

FurryOnTheInside

Well-Known Member
Joined
Sep 23, 2013
Messages
3,425
I agree charging is their biggest down side,Like anything some users will have their issues,I've had r/c balence chargers for decades now and they last and work well for me.The hyperion system I'm currently using is just over 10 y/o and it runs of a 750 w computer power supply that I just bridged everything to out put terminals added to the case with a switch cost me like 35 bucks the charger was like almost $300 but it can charge 2 6cell packs at once at up to 10a out put for each.Batteries when it come to rechargeable chemistry's have allways was been sketchy,when we used ni-cad prior to the lithium chemistrys they blew up,caught fire and stuff as well when misused yet I've never even poped a cell.I like the li-po for weight, size and power,price is not bad because there is no bms in the pack,you can use a bms to be able to use a simple charger but in most cases it's the bms that holds back amp levels so I dont use them LOL.There are lot's of ways to go it's fun learning,playing with the electric's with deep pocket's I believe the sky is the limit!
I've read some good, mixed, and bad reviews and experiences of the Hyperion chargers too!.. and with the price, and the bulk of the PC power supply it just seems impractical for me.
But now you go and give me another option to consider (and more to research!) by saying that a BMS will allow (slow) charging with a simple and affordable and portable charger! o_O:X3:

If this charging system can be safe and portable then I may just have to re-re-reconsider the Li-poly after all. :coffee::alien:
I will see if I can find a recommended BMS and charger (with a link that's still valid!) then maybe we're back in business with the Li-poly. :coffee::unsure:
 

FurryOnTheInside

Well-Known Member
Joined
Sep 23, 2013
Messages
3,425
I wonder if your thing about the front wheel locking up from the regen in a big concern. I think a lot of other ppl do it and i havent heard that much about this issue. I believe you dont need to worry about backcurrent because there are stud diodes in the controller to prevent any backflow i think. What u need to worry about is i just found out that buying off alibaba is a pita. I was looking at shipping costs and see u have to find a shipping company and get quotes and the lowest i could find was $400 to ship this $100 ebike kit to the USA from jinsuang china. And by boat it was like $1000 because off tarriffs and import fees and customs bonds and all this sh*t. like wtf y so much money!!!! See Alibaba only works if u are buying enough to fill a shipping container. I was thinking abut mass producing these bikes in scale as a side job and now i am a little upset b/c amazon prices are a lot higher and i know that by running it through the rear wheel, thats extra time and sometimes the gear shifter and the gear cassettes don't work perfectly ie a 6speed cassette and 7 speed shifter could make a disaster if you put it in 7 at x speed.
But good luck with your build. The only real issues i think of like the ppl who buy a 3000w cyclone kit and have a 48v 20ah battery. The battery can only provide 1000w peak so u are only getting 1/3 of the motors potential or 1/3 the top speed.
The 20Ah battery can only supply 20A at 1C. To safely discharge faster you can use cells with a high C rating, like the Li-poly packs commonly used in radio controlled gadgets.
 

Frogslayer

Active Member
Joined
Jan 20, 2019
Messages
484
I wonder if your thing about the front wheel locking up from the regen in a big concern. I think a lot of other ppl do it and i havent heard that much about this issue. I believe you dont need to worry about backcurrent because there are stud diodes in the controller to prevent any backflow i think. What u need to worry about is i just found out that buying off alibaba is a pita. I was looking at shipping costs and see u have to find a shipping company and get quotes and the lowest i could find was $400 to ship this $100 ebike kit to the USA from jinsuang china. And by boat it was like $1000 because off tarriffs and import fees and customs bonds and all this sh*t. like wtf y so much money!!!! See Alibaba only works if u are buying enough to fill a shipping container. I was thinking abut mass producing these bikes in scale as a side job and now i am a little upset b/c amazon prices are a lot higher and i know that by running it through the rear wheel, thats extra time and sometimes the gear shifter and the gear cassettes don't work perfectly ie a 6speed cassette and 7 speed shifter could make a disaster if you put it in 7 at x speed.
But good luck with your build. The only real issues i think of like the ppl who buy a 3000w cyclone kit and have a 48v 20ah battery. The battery can only provide 1000w peak so u are only getting 1/3 of the motors potential or 1/3 the top speed.
Your still getting the same top speed, this is determined by volts. Your getting 1/3 of the torque and probably 3 times the heat generation.
 

FurryOnTheInside

Well-Known Member
Joined
Sep 23, 2013
Messages
3,425
I'm considering trying 4 of these.View attachment 85906
IMHO
Its worth waiting and just saving up a bit more for a lithium battery.
The weight and bulk and lack of actual useable Ah is too much. You "will" be unhappy with them and end up buying lithium later to solve the problems of SLA, and then you're just buying twice.

I have five 12v SLAs in my 60v 500W e-moped, but it is for occasional use and very local range. It won't do daily commuting or pleasure rides, and I'm not keeping it once I get a lithium powered bicycle going.
 

Frogslayer

Active Member
Joined
Jan 20, 2019
Messages
484
I don't know if i could justify buying a 250 dollar charger. Lithiums kind of suck to use and keep balanced but if you need the power you need it. I have all kinds of lipo rc packs for trucks and planes and quads but my charger will only charge 6s
 

FurryOnTheInside

Well-Known Member
Joined
Sep 23, 2013
Messages
3,425
I don't know if i could justify buying a 250 dollar charger. Lithiums kind of suck to use and keep balanced but if you need the power you need it. I have all kinds of lipo rc packs for trucks and planes and quads but my charger will only charge 6s
So use a common 18650 li-ion in-frame or rack pack. The charger doesn't cost much, isn't complicated, or large. The weight and bulk is still a lot less than SLA for the equivalent usable Ah.
 
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