Bernel wrote: ↑
Mar 31 2019 3:20pm
Mandres wrote: ↑
Jan 12 2019 1:12am
Hi, awesome project! I was just wondering if the Mobipus controller is still in the pipeline? I'm debating between their 600A model or a Sevcon gen4 and wondering if you might have experience with both?
Batteries are still a question mark for me too. I'm considering Chevy volt cells, or possibly a 32s2p custom pack of Yinlong LTO 40ah cylindrical cells.
I did not get the Mobipus, in the end I bought a Sevcon Gen4Size6. I fitted this to the bike October 2018 and the results were encouraging. I still need to tune the throttle though. Work will start to pick up now since I have cancelled work on another project. I will be looking to replace the ME0913 with a ME1507 and increasing the pack voltage to 99.9V nominal.
I don't know what is your progress so far with your battery, but if you're not decided yet I suggest you to go for A123 pouch cells pack if you can.
A friend of mine and myself are using those cells on our motorcycles, mine is only drawing 16KW with a sabvoton controller on a 72V 40Ah pack, but his bike is drawing more than 42KW from the same pack with a Mobipus controller and it works perfectly fine.
Those packs are probably a little bit heavier than other chemistries, but not by much if you factor in the loss of capacity after a year and the fact that they tolerate high discharge rates so you don't need to go too high on capacity. In our case, the battery weights 25Kg for 72V 40Ah (23S 2P) and we had it reliably push 600A battery / 1000A phase.
They have a very low internal resistance, so they don't sag much under load and they are able to supply gigantic amounts of currents in both peak and continuous reliably so you don't need to invest on crazy capacities just to make your bike run. They are extremely safe and tolerate deep discharges until 2V per cell, they have a quite long life cycle and they almost don't self discharge so you can store them for years without worrying they will die. Basically this battery is a no brainer: install an Ant BMS bluetooth and you're good to go.
We bought those second hand, no idea how many cycles they had, but they are still going very strong. I have mine for more than a year now, doing around 30-40 km every day to go to work with a quite aggressive riding style: no problem at all. They were also very, very cheap when bought second hand (in my case around 370 Usd for a 72V40Ah battery), but that might largely depend on wherever you live.
I'm pretty sure you could fit at least 120V 40Ah in this bike, you have quite a bit of space. That would be a very impressive machine.