Bike Forums

Bike Forums (http://www.bikeforums.net/forum.php)
-   Utility Cycling (http://www.bikeforums.net/utility-cycling/)
-   -   (Cross post): Electric Assist batteries for cargo bike (http://www.bikeforums.net/utility-cycling/912072-cross-post-electric-assist-batteries-cargo-bike.html)

Jewel 09-09-13 04:18 PM

(Cross post): Electric Assist batteries for cargo bike
 
Am doing some initial research into getting a cargo bike with an e-assist battery. How does the battery perform in cold (LOW) temperatures for winter commuting? Specifically wondering how the battery does in low temperatures as well as when a bike is fully loaded with groceries in cold/wet conditions. Is it more sluggish? Is there anything special one has to do to the battery to protect it in cold/wet winter conditions?

(this was cross posted in "Winter sub-forum"

Ranko Kohime 09-09-13 06:31 PM

If the batteries are cold, as in sat out overnight cold, you will see reduced power & shorter range, perhaps 50% or less of summertime, depending on temperatures. This generally is not permanent, and the batteries will bounce back in the warm weather. Lead-acid will be much more prone to this than Lithium, but Lithium will still experience it to a degree.

If you cannot bring the bike in out of the cold, then consider any arrangement that allows you to unstrap the batteries and take them inside. It takes several hours for batteries to acclimate going from warm to cold, and they generate internal heat when being used, so an hour or so of use out in the cold will not reveal too much performance degradation.

wahoonc 09-10-13 03:35 AM

Define cold...

Batteries lose performance in cold weather, taking them inside at night helps. On the flip side a cold battery will take a charge better than a warm one.

Aaron :)

Jewel 09-10-13 09:14 AM

Okay. Good to know. Didn't consider the common-sense thing about the battery getting warmer while in use --thanks for the reminder! I hadn't thought of that. I guess I was just thinking about the extra weight of the cargo possibly making the bike's battery run sluggish (more wt + cold temps =more sluggish), but it doesn't sound like that'll be an issue.

Aaron, "Cold" here in the high desert is 5 degrees Fahrenheit (without windchill factor considered)

turbo1889 09-10-13 10:47 AM

Quote:

Originally Posted by Jewel (Post 16050516)
. . . "Cold" here in the high desert is 5 degrees Fahrenheit (without windchill factor considered)

Shouldn't have too much trouble if it only gets that cold (-30F where it can get where I am is a whole different story) if you stick with using a Lithium based battery chemistry (LiFePO4 packs built from hard case prismatic or cylindrical cells not soft poly cells is currently my favorite all around battery choice). I would suggest staying away from lead-acid and NiMH battery chemistry if it often gets that cold in your area, especially if you don't take the battery off the bike and bring it inside where its warm when its not in use. (If it only gets down to +5F at the coldest then with a Lithium based battery chemistry you should be able to get away with not bring in the battery where its warm when not in use, it will just be a little sluggish when you first start out until the battery warms itself up due to the heat created internally during use.)

wahoonc 09-10-13 06:01 PM

Quote:

Originally Posted by Jewel (Post 16050516)
Okay. Good to know. Didn't consider the common-sense thing about the battery getting warmer while in use --thanks for the reminder! I hadn't thought of that. I guess I was just thinking about the extra weight of the cargo possibly making the bike's battery run sluggish (more wt + cold temps =more sluggish), but it doesn't sound like that'll be an issue.

Aaron, "Cold" here in the high desert is 5 degrees Fahrenheit (without windchill factor considered)

For most Lithium Ion batteries that is doable, a bit sluggish, but will warm up as you use it. Cold where I live is 25*f :D we dig out the long handled drawers at 40* :P

Aaron :)

fietsbob 09-13-13 04:01 PM

charging makes heat in the battery..


All times are GMT -6. The time now is 09:03 AM.