How did it perform in the cold? I've noticed sla's start slowing down their rate of discharge when it gets around 50F.
Well, fortunately we've had rather warm weather so far this season so I've not had opportunity to test the extreme range of cold LiFePO4 operation... which while there's some disagreement, seems to be around -4ºF (-20ºC) to -13ºF (-25ºC) before there's a noticeable detrimental effect & even then there's some conflicting reports, claiming LiFePO4's will "warm themselves" with some attempted use even at these low temps... but that was from a battery vendor so I dunno how much to credit it. Even if so, there's also been some reports of BMS shutdowns due to the voltage/amperage irregularities and this seems completely credible - depending ofc on the sensitivity of the BMS used, but I suspect when I run into trouble it'll be most likely due to the BMS and not so much the reduced range/speed of cold batteries...
...but from me - it's all still guesswork & theory, the temps around here have still mostly been in the 20ºF to almost 40ºF (-6ºC to 4ºC), the coldest I've ridden in with the ebike for any length of time so far was 15ºF (-9ºC) in which the pack was exposed for about two hours total, with no apparent effect whatsoever on it's capabilities.
There are other factors than battery chemistry that reduce the preformance, annoyances like the need for knobby tires and their rolling resistance, the not insignificant effect of thickened lubricants, the pronounced effect of snow weight/resistance - and admittedly my stamina, wind chill and exhaustion also taking it's toll on range/speed & general "preformance" so even aside from the capabilities of cold LiFePO4s, there's zero chance I'll see anything like my full 30 mile summertime range between charges lol
so how did mongo handle in the snow? i bet that back tire you could make spin big time
Kinda tough to say really as this was the first real snowfall we've had - I've lost my groove so to speak, I'm out of practice & clumsy, it'll take me a bit to regain my snow riding abilities, doubtlessly entailing a crash or two to remind me... same ol' story as all the previous winters heh, guess I'm a slow learner. Whoever said "it's like riding a bicycle" (skill once learned, never forgotten) obv had no idea what they were talking about lol
There were however some things I noticed right away, the primary being that it preformed
far better than I expected given the reduction of HP compared to the gasbikes I've previously run - in fact so far the HP difference seems to have little effect given the reduced speed required to maintain stability, while the gasbikes had the capability of going faster due to their greater power, I couldn't use that speed given the road conditions... so the effect (for me) is the ebike and the gasbike preform the "same" ...which I hadn't anticipated in the slightest.
If anything the lessened HP and greater weight on the rear tire have reduced wheel spin, which is wonderful for stability and acceleration & combined with another unanticipated effect, that of the
extremely smooth and predictable application of power - makes for a far easier bike to ride on snow & ice, or at least to start out & get up to speed. Due to the weight & balance issue caused by my battery pack being over the rear wheel, once up to speed the front wheel is a bit more squirrely than I remember the gasbike's being... or I'm just completely out of practice, hard to tell at this point & it's prolly both anyway.
There's a lot of variables, things that differ between this ebike and the gasbikes I've run in the winter - not just relative power, but weight & balance, ergonomics, tire tread (lug pattern) even braking (disc vs rim) & with my appalling degradation of skill, makes it very difficult to say with certainty which I "like" better or why... but so far I'm very,
very impressed with Mongo's overall ability to deal w/the white stuff *shrug*
Only time will tell if I'll remain as impressed lol & thus the "& so it begins..."