ichiban
100 W
Kind of new here, might not post correctly - sorry for that in advance.
I recently (2-month) converted my entry-level 27.5-in Bianchi 27.1 MTB into an e-bike using BBSHD 48V 1000w kit from AliExpress
View attachment 5
Battery :
Powered by 14s7p 18650 harvested from scrapped laptop batts and DIY into a batt pack. Bulky and heavy (of course! 14s7p = 98cells + caps + stainless bus + nuts + bus bar +..+..+ etc.) but seems with adequate power up to now. I managed to put 500+ km on the bike in about two months. Range per charge is not bad 50km+ with little to moderate pedaling. The BMS is dumb type (about USD20.- from AliExpress again) and I have no clue if it ever balances any cells groups at all, regardless of the bike non-using-period of 3-4 days. The Hi - Lo batt voltage are still 0.2-0.3 V among groups (actually, I spotted about 4-5 groups with low volts compare to the rest) and getting worse with each charge. My charger is Lunar 5-amp 80/100% charge cap and looks like I get less and less capacities when the Lunar charger cut-off. I really never know whether the BMS is still working since no sign if it is alive except that it did not short my cells pack out ... yet.
View attachment 3
Energy used :
Most of my rides are in a big city, flat terrain and normal to congested traffic on public roads.
With 80-90% pedaling, I got 6.xx-7.xx wh/km at average speed of 30+ to 50+km/h, PAS #4-#5 out of 9 levels.
With throttle mostly and little pedaling (less than 5% of the time), I might get 12.xx wh/km.
The power meter I use is the 130-amp GT Power watt-meter (USD10.- or so - a Turnigy clone ?) connecting directly from the batt and before anything else in the system ; controller, motor, display, etc.
Is my 7 wh/km too good to be true ? If yes, should I scrap the 130-a GT Power and change to something else ? What is the recommended watt meter ? I try to avoid that Cycle Analyst since it is waaaay out of my budget. Actually, I'm reconsidering....
But if the above wh/km is realistic, I am just realizing that e-bike is the most practical, most energy-efficient way of transportation there is.
View attachment 2
Future :
Since my current pack sags a lot and I got less and less capacity with each charging. I know the harvested cells are old (some cells might be 10+ yrs old) but this is my first DIY pack and for the sake of getting it done cheaply. Even if I get a smart BMS with all that fancy cut-off/ hi-lo etc. functions, but my pack is about to come to its life span not too long from now ? I learned a bit and agreed with some folks in this ES forum said that DIY pack from old laptop cells are a good way to learn with expensive tuitions ... been there, done that...LOL.
A new pack from EM3EV looks good, that small triangle hard-pack 14S6P with Samsung 35E in it (84-cell of 1000+ wh) - most bang for the bucks, still cost me USD569.- + shipping. Is this a good choice ? I'm not a hard-core rider/jumper just ride for fun and commute when possible.
Might be lengthy but like getting the burden out of my chest asking these questions in the ES forum. Since there is almost nobody around here to ask. The bike mechanics I went to did not even know what I was talking about regarding e-bike. Thanks a lot for any comments and suggestions.
P.S. : I greased the internal gears, all moving parts within the Bafang motor and my front+rear wheels with Mobilgrease 28 during assembling as recommended by many users. When I first opened up the BBSHD, it had very little lubricant in it - almost dry. It is now running smoothly and quiet after 500+km.
I recently (2-month) converted my entry-level 27.5-in Bianchi 27.1 MTB into an e-bike using BBSHD 48V 1000w kit from AliExpress
View attachment 5
Battery :
Powered by 14s7p 18650 harvested from scrapped laptop batts and DIY into a batt pack. Bulky and heavy (of course! 14s7p = 98cells + caps + stainless bus + nuts + bus bar +..+..+ etc.) but seems with adequate power up to now. I managed to put 500+ km on the bike in about two months. Range per charge is not bad 50km+ with little to moderate pedaling. The BMS is dumb type (about USD20.- from AliExpress again) and I have no clue if it ever balances any cells groups at all, regardless of the bike non-using-period of 3-4 days. The Hi - Lo batt voltage are still 0.2-0.3 V among groups (actually, I spotted about 4-5 groups with low volts compare to the rest) and getting worse with each charge. My charger is Lunar 5-amp 80/100% charge cap and looks like I get less and less capacities when the Lunar charger cut-off. I really never know whether the BMS is still working since no sign if it is alive except that it did not short my cells pack out ... yet.
View attachment 3
Energy used :
Most of my rides are in a big city, flat terrain and normal to congested traffic on public roads.
With 80-90% pedaling, I got 6.xx-7.xx wh/km at average speed of 30+ to 50+km/h, PAS #4-#5 out of 9 levels.
With throttle mostly and little pedaling (less than 5% of the time), I might get 12.xx wh/km.
The power meter I use is the 130-amp GT Power watt-meter (USD10.- or so - a Turnigy clone ?) connecting directly from the batt and before anything else in the system ; controller, motor, display, etc.
Is my 7 wh/km too good to be true ? If yes, should I scrap the 130-a GT Power and change to something else ? What is the recommended watt meter ? I try to avoid that Cycle Analyst since it is waaaay out of my budget. Actually, I'm reconsidering....
But if the above wh/km is realistic, I am just realizing that e-bike is the most practical, most energy-efficient way of transportation there is.
View attachment 2
Future :
Since my current pack sags a lot and I got less and less capacity with each charging. I know the harvested cells are old (some cells might be 10+ yrs old) but this is my first DIY pack and for the sake of getting it done cheaply. Even if I get a smart BMS with all that fancy cut-off/ hi-lo etc. functions, but my pack is about to come to its life span not too long from now ? I learned a bit and agreed with some folks in this ES forum said that DIY pack from old laptop cells are a good way to learn with expensive tuitions ... been there, done that...LOL.
A new pack from EM3EV looks good, that small triangle hard-pack 14S6P with Samsung 35E in it (84-cell of 1000+ wh) - most bang for the bucks, still cost me USD569.- + shipping. Is this a good choice ? I'm not a hard-core rider/jumper just ride for fun and commute when possible.
Might be lengthy but like getting the burden out of my chest asking these questions in the ES forum. Since there is almost nobody around here to ask. The bike mechanics I went to did not even know what I was talking about regarding e-bike. Thanks a lot for any comments and suggestions.
P.S. : I greased the internal gears, all moving parts within the Bafang motor and my front+rear wheels with Mobilgrease 28 during assembling as recommended by many users. When I first opened up the BBSHD, it had very little lubricant in it - almost dry. It is now running smoothly and quiet after 500+km.