Noob question, if I have a stock very new 10s3p pack and wanted to go to 4p what’s the best option for someone who doesn’t want to do any welding? If I got a 10s1p pack with the same cells is that an option? If I didn’t get a new BMS to manage the pack together would I need two charge ports and is that not advised?
Is removing existing BMS and replacing easier than I think? Or am I better off taking it somewhere that will repack and replace BMS (not many options here in NZ)?
Just get a 10S1P pack and run them in parallel. Yes, you need two BMSs (each battery should have one) and it’s best if they’re the same cells but if not, mention which ones you’re considering.
You can use just 1 charge port. Or two. (But not one for each battery, just 2 wired in parallel.)
HOWEVER, the packs MUST be at the same voltage when you connect them together (or within 0.1V). Once they’re connected together in parallel, don’t disconnect them. At all.
Looking for anyone and everyone that has put a vesc in a prebuilt ebike. Want to know what performance did you see. I know top speed isnt going to change. Im more curious about acceleration as the controller won’t be locked @ 20a.
It’s a 20" 500/750/1000w bafang hub, 13s. It tops out around 32mph. From my understanding, I should see a difference in acceleration but all Ive ever had to base that off of is inrunner and outrunner motors. I’ve always heard crap about hubs so never really messed with them. Would love to get a better understanding of the adventure this build holds.
VESC is bad on large hub motors, but I’ve never tried a bicycle hub motor. But in general, the commutation and motor detection software seems to be really bad for those types of motors.
I’ve put a few VESCS in ebikes. First was 750w geared hub motor on 13s. Used a 75100 and ran it around 50A based on the roughly 16awg phase wires. Very quick off the line. Davega can be used on the handlebars, or a Metr with a phone mount.
Second was a 1500w direct drive leaf hub motor on 20s at 120A. Use the 2kg outrunner detection method instead of the hub setting for better results and run firmware 5.3 or newer. Field weakening can be used to gain some top speed at the cost of range and controller heat.
Which is the final big consideration. It’s easier to pull continous current on an ebike and they will overheat a controller much faster than a dual motor esk8. Use a controller with a good cooling design and figure out how to mount it in airflow while keeping it somewhat waterproof. The Unity or Stormcore in super single mode would be a great choice. Also the new 75100 aluminum pcb, or the 75200 would preform really well thermally.
The 4.12 or the old 75100 boxy version would be bad choices as they overheat very quickly, unless you keep the amps around 30-50A.
PAS is available in 5.3 and a few have set it up, but there is very little info on it.
Alternatively the pins can be assigned manually in the model’s .h file if you want to use something other than the UART pins. See the hwconf/hw_luna_bbshd.h for an example
Looking for some info from anyone with experience with the @Kaly barrel dampers. I’m ~220 with all of my gear on. Thinking medium all around is about right but maybe med up front and hard in the back? The board is presently a carver and may at some point be convertes to a true AT. All opinions welcome
LiPo batteries are heavily optimized towards maximum performance, and one of the things that gets neglected/reduced in the pursuit of that performance, is cycle life. The cells tend to not last as many cycles before experiencing noticeable degradation.
One of the things that you can do to avoid this is to not charge the battery as fully, and not to discharge it as far. So instead of going with 4.20 and 2.50 volts (common datasheet numbers for Li-ion and LiPo cells), only going down to 3.2 or even 3.7V/cell should help make your batteries last longer.
It’s all a tradeoff though, because setting super-conservative cutoffs means you have less effective capacity/usable energy to work with, for a given size of battery. It’s just a judgement call you have to make, whether you want all the range now, or all the cycles later, or somewhere in between.
