Phil, I agree with what you said, except that there is a chemistry with WAY higher energy density than Li ion. Both in energy per volume and energy per weight, though the latter is lower, because the main electrode is made of Iron. Power density is much lower and besides that, the cells need air and electrolyte pumped, so it is not an easy self contained battery like Li ion, but the company I joined recently, Form energy, develops utility sized Iron-air batteries. With about 4 times higher energy than comparable Li containers. That was one of the reasons I joined Form energy (short: Fe) instead of Tesla. We need different battery technologies. Cor.
On Sun, Oct 5, 2025, 4:33 PM (-Phil-) via EV <[email protected]> wrote: > You also will not find any other chemistry that can equal the energy > density of ternary lithium. LFP is probably close enough for an eBike and > relatively safe, though when charging below 0°C (32°F), the charge current > must be reduced to 0.1C, if below -10°C (14°F) it must be reduced to 0.05C, > and below about 18°C (0°F), you should not charge at all. They will > continue to discharge ok, but with reduced performance. But I can't see > anyone wanting to ride an eBike at those temperatures! Just charge your > packs inside where it's warmer and you'll be good to go. > > You can buy pre-made LFP packs in eBike voltage ranges with built-in BMS on > Aliexpress. > > On Sun, Oct 5, 2025 at 4:15 PM Cor van de Water via EV <[email protected]> > wrote: > > > For deep freezing performance, there are the flooded NiCd cells, only > 1.2V > > per cell, but well liked for snowblowing ElecTraks, original service life > > is typically aircraft starter batteries. Model nr varies, often referred > to > > as BB600. Quite a weight for eBike, so maybe look for standard round NiCd > > or NiMH batteries. > > Note that many battery types cannot stand cold when discharged and in > > particular Li cells essentially become worthless when charged at very low > > temps, they essentially block all the passages where ions move inside the > > cell, quickly dropping the capacity to store energy. > > Cor. > > > > On Sun, Oct 5, 2025, 4:00 PM t ray via EV <[email protected]> wrote: > > > > > I'd like to buy or build an eBike. Problems include our local > > > deep-freezing winters, and the combustible lithium batteries. I have > no > > > desire to build a soil-covered bunker (doghouse) in the back yard > where I > > > can store and charge lithium batteries safely. > > > So far, the best I know is the LiFePo chemistry, but the commercial > > > products are not the equal of lithium batteries. I keep seeing > "better, > > > faster" options in development, but somehow, never this year. > > > Does anybody know a source for batteries of near-equal or better > > > performance than lithium? Since I don't need very many, I am willing > to > > > look at more expensive options if they can do the job here. > > > Thanks. > > > -------------- next part -------------- > > > An HTML attachment was scrubbed... > > > URL: < > > > > > > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20251005/6b5e0fa2/attachment.htm > > > > > > > _______________________________________________ > > > Address messages to [email protected] > > > No other addresses in TO and CC fields > > > HELP: http://www.evdl.org/help/ > > > > > > > > -------------- next part -------------- > > An HTML attachment was scrubbed... > > URL: < > > > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20251005/1f311ec8/attachment.htm > > > > > _______________________________________________ > > Address messages to [email protected] > > No other addresses in TO and CC fields > > HELP: http://www.evdl.org/help/ > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20251005/f08434ea/attachment.htm > > > _______________________________________________ > Address messages to [email protected] > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20251005/9b7f07da/attachment.htm> _______________________________________________ Address messages to [email protected] No other addresses in TO and CC fields HELP: http://www.evdl.org/help/
