My current project is getting my 3d printing stuff all set up. I’m building a Voron V0.2 but I need to print some more parts for it, but other than that I only have an ender 3. So I’m modifying and tuning the Ender to produce high enough quality ABS/ASA parts for me to be satisfied using in the Voron. Not a difficult project per-se but I’m coming out of a depression that along with my day job taking time away led to a long period of not doing any projects, so this is meant to be a refresh for my project brain.
I also want to build an e-bike with a somewhat unconventional drive-train, where it’s configured like a series hybrid: pedals drive a generator which drive the motor with a boost added by the batteries. I got the idea because most e-bikes either use a pedal cadence sensor to activate automatic assist (cheap but the assist power doesn’t scale linearly with input power which I don’t love) or a power meter (expensive because they use strain gauges to measure torque at the pedals, but nice linear proportional assist). I have no idea if this idea will be better overall, I’m trading a torque sensor for a whole ass motor which won’t be light or cheap either, but the idea of it scratches my brain in a nice way :) Also, it means I don’t need a whole multi-speed chain drive to achieve different gear ratios between the pedals and the wheel.
Those little RISC-V micros seem sweet and the existence of open source toolchains for them makes me really happy! That sounds like a great project!
Damn, both projects are cool AF. I remember building a Prusa i3 clone some 10 years ago with a buddy, was nice (I regret that now, he turned out a Zionist lmao). And the bike thing sounds great, I’ve been trying to muster the courage to spot-weld 18650 batteries with nickel strips and a cheap aliexpress mini spot welder for such projects, but I’m afraid of setting myself on fire!!
If you manage to get either of those running, you could make a post at c/DIY, I’d love to scroll through it :)
Spot welding batteries seems simple enough but not wanting to start a lithium fire is always good motivation to get cautious. I think I’ve heard that double pulse spot welders are the best way to do it?
Do you have any projects for the batteries? Recycling cells or making custom packs?
Primarily making custom packs, just because you guarantee that you get good cells from a good supplier at a low price. When you buy ebike batteries, cheap ones are often with shitty cells, and expensive ones are just overpriced.
I think what I would get excited about is using different chemistries. Like LiFePO4 for the long lifespan and better temperature tolerance. Or LTO for super long lifespan and really fast charging. Most e-bike packs I see are standard NMC Li-ion chemistry. And yeah, a high quality LiFe pack I found was really expensive. I have some used/recycled LiFe battery packs that were cheap and had a low cycle count, they would probably be good candidates.
For LiFePO4 I’d just get one of these big bulky car-like batteries I guess, in a comparably more powerful ebike. Kinda turning it into a motorbike hahaha it’s just these big LiFePO4 batteries are so freaking cheap, they go for like 100€/kWh
Yeah I have some of those, a few kWhr of them actually XD. The voltage is low for what most e-bike motors are wound for though. The batteries i was talking about before are some smaller 25.6V batteries where i could easily throw three in series to get up to typical e-bike voltage. Plus the 12.8V car style batteries would be really bulky to put in a bike frame. I could always take them apart and use the cells though.
Hmmm yeah I never thought about the voltage. I guess that could be solved by buying a 24V pack or putting two smaller 12V ones in parallel. I just freaking love how affordable LiFePO4 batteries have become
I’m guessing you meant to say in series? Yeah the monetary cost is great but I believe the human cost is the biggest positive, given that they don’t require cobalt.
My current project is getting my 3d printing stuff all set up. I’m building a Voron V0.2 but I need to print some more parts for it, but other than that I only have an ender 3. So I’m modifying and tuning the Ender to produce high enough quality ABS/ASA parts for me to be satisfied using in the Voron. Not a difficult project per-se but I’m coming out of a depression that along with my day job taking time away led to a long period of not doing any projects, so this is meant to be a refresh for my project brain.
I also want to build an e-bike with a somewhat unconventional drive-train, where it’s configured like a series hybrid: pedals drive a generator which drive the motor with a boost added by the batteries. I got the idea because most e-bikes either use a pedal cadence sensor to activate automatic assist (cheap but the assist power doesn’t scale linearly with input power which I don’t love) or a power meter (expensive because they use strain gauges to measure torque at the pedals, but nice linear proportional assist). I have no idea if this idea will be better overall, I’m trading a torque sensor for a whole ass motor which won’t be light or cheap either, but the idea of it scratches my brain in a nice way :) Also, it means I don’t need a whole multi-speed chain drive to achieve different gear ratios between the pedals and the wheel.
Those little RISC-V micros seem sweet and the existence of open source toolchains for them makes me really happy! That sounds like a great project!
Damn, both projects are cool AF. I remember building a Prusa i3 clone some 10 years ago with a buddy, was nice (I regret that now, he turned out a Zionist lmao). And the bike thing sounds great, I’ve been trying to muster the courage to spot-weld 18650 batteries with nickel strips and a cheap aliexpress mini spot welder for such projects, but I’m afraid of setting myself on fire!!
If you manage to get either of those running, you could make a post at c/DIY, I’d love to scroll through it :)
Spot welding batteries seems simple enough but not wanting to start a lithium fire is always good motivation to get cautious. I think I’ve heard that double pulse spot welders are the best way to do it?
Do you have any projects for the batteries? Recycling cells or making custom packs?
Primarily making custom packs, just because you guarantee that you get good cells from a good supplier at a low price. When you buy ebike batteries, cheap ones are often with shitty cells, and expensive ones are just overpriced.
I think what I would get excited about is using different chemistries. Like LiFePO4 for the long lifespan and better temperature tolerance. Or LTO for super long lifespan and really fast charging. Most e-bike packs I see are standard NMC Li-ion chemistry. And yeah, a high quality LiFe pack I found was really expensive. I have some used/recycled LiFe battery packs that were cheap and had a low cycle count, they would probably be good candidates.
For LiFePO4 I’d just get one of these big bulky car-like batteries I guess, in a comparably more powerful ebike. Kinda turning it into a motorbike hahaha it’s just these big LiFePO4 batteries are so freaking cheap, they go for like 100€/kWh
Yeah I have some of those, a few kWhr of them actually XD. The voltage is low for what most e-bike motors are wound for though. The batteries i was talking about before are some smaller 25.6V batteries where i could easily throw three in series to get up to typical e-bike voltage. Plus the 12.8V car style batteries would be really bulky to put in a bike frame. I could always take them apart and use the cells though.
Hmmm yeah I never thought about the voltage. I guess that could be solved by buying a 24V pack or putting two smaller 12V ones in parallel. I just freaking love how affordable LiFePO4 batteries have become
I’m guessing you meant to say in series? Yeah the monetary cost is great but I believe the human cost is the biggest positive, given that they don’t require cobalt.