Climate change and batteries

I have to agree it's time for another mini ice age.
It sounds as though when this happens, as it does every so often the change comes suddenly, and in the past has led to mass extinctions.
Tropic north Queensland will likely no longer be the nice Quiet and sparsely populated place I enjoy, so I hope it don't happen in my life time.

That depends on the battery technology and the temperature. Obviously, once you hit -40º it doesn't matter if it's ºC or ºF.

Standard flooded cell batteries will freeze, but it takes prolonged exposure for it to happen.

SLA, or sealed lead-acid batteries don't use a liquid electrolyte, it's usually a gel and has a lower freezing point, or the liquid is held in a fibrous media like fiberglass (that's where you'll hear the term 'glass-mat').

Oddly, a cold battery often lasts longer in use than a warm one. The temperature regulates the rate of chemical reaction (which once wet-up never stops until there is nothing left to react to each other). In the summer months it was difficult to keep cycling our product through the charging station at the battery warehouse sometimes due to the amount we had to keep charged with only 5 chargers. We kept records on the pallets of date/charge and you could see how quickly they would drop off in the summer vs. the winter.

[I just have to add in, the "old farmer's tale" of a battery left sitting on concrete dying is just that... My co-worker/boss and I have tested it.. no discernable change in voltage from the rest of the batch it came from sitting in racking on pallets over a 6-week test.. we theorized that that problem comes from a battery left on the concrete slab floor of an outbuilding during a Canadian (or northern US) winter actually freezing or coming close to it by thermal conduction.. seriously, if the acid doesn't weep out of the plastic case's side, calcium from concrete can't leech in that way to kill the battery... Sorry for the ramble here.]

{For reference, I worked for a "major world wide" transportation battery company for around 10 years until last August.}

The worsening economy helped trigger motorbike kit sales. Rising fuel prices also trigger sales, but gasoline prices have stabilized.
Affordable but well made electric kits like the base Hill Topper have also probably taken some gas bike sales. The Hill Topper is only a 250w kit and the throttle is merely a button that is attached to the handlebar with velcro. However, the kit installs easily and it works for $400 (SLA batteries included). Add $100 for Lipo.
The new mid drive shifter electric kits have also taken some gas bike sales. They offer some mechanical complexity that appeals to the same guys that buy gas kits.
I still think the economy and fuel prices affect gas motor kit sales more than innovation in the electric kits.

Part of the problem with gas bike sales as I see it, is that less and less people know how to work on motors and mechanical things these days.

Perhaps it's something to do with the different energy storage technologies.. I worked with lead-acid almost exclusively, so can't say if Lithium or hydrogen cells react differently from personal experience (except for power tool battery packs, which never seem to have more than 3/4's of the job in them for me no matter how new or well charged they are). The logic regarding chemical activity should still apply, but then again if I truly understood all of it I'm pretty sure I'd have a nice weekly paycheque.

There has been work on super capacitors, which are unaffected by low temperatures. I don't understand these things, but I have heard mutterings of them being The Next Big Thing.

This gives some insight into the myths, legends and facts of batteries.

http://www.google.ca/url?sa=t&rct=j...=fr0zTzrlJps4y4flNEYCrw&bvm=bv.66917471,d.cGU

Steve

LiFePO4 batteries have a very wide working temperature range, from approximately -4° to 150° F according to some manufacturers... although it's difficult to ascertain their exact parameters due to the abundance of conflicting information and the additional complexities of the advanced battery management systems. When a LiFePO4 pack "fails" due to cold, it's usually the BMS shutting down. Everything is effected by extreme cold to some extent and LiFePO4s are no exception - but some BMSs will shut down to protect the cells with only the tiniest variation in available current, where a SLA will "sag" and limp along for a little while due to the cold, a BMS may shut down the pack with only a 10% or less drop, although the LiFePO4 battery itself is almost completely unaffected.

Having said that I'm fortunate enough to have a BMS less picky about such minor variations, my range is reduced - but it's got a lot more to do with my intolerance for extreme cold then the ebike's. There's also the additional load of rough surface conditions, it does take more juice to plow your way through icy snow pack with knobbies then hum along on dry pavement with street slicks.

Generally speaking for our application it's a bit of a moot point - in any temperature range you'd be willing to ride in LiFePO4s seem to work just fine. I've ridden in -30° F more then I'd care to mention yet I've not had any undue issue with range, reserve or charge. I do charge & store it indoors overnight, but it's oft left outside for however long whenever I get where I'm going other then home, it's not failed me yet lol;

DDbike said:

I believe that the climate has been changing on the earth for about 4 and half billion years ...

I watch sunspot activity .... and the latest thinking is that we are headed towards a cooling period .... a mini ice age ....

... batteries don't work well in colder temps ....

... so ... i am thinking gas bikes will come back into the trend and battery bikes will slip ...

... i am new to gas bikes and this forum ....

.... it seems that the posts were more frequent several years ago ...

...are we in a gas bike slump?

...

Click to expand...

I wouldn't call it a gas bike slump as much as a eBike surge.

I'm pretty sure there's still time to buy, and wear out a couple of eBikes before the ice age sets in.