My main transports are EZip "Trailz" electric assist bikes. They come stock with 10AH SLA batteries, which are very poor, to begin with, but suffer mightily when cold, and forced to push through snow, or slush.
Actual usable output is merely 6AH, but when cold, possibly only 3ah. Unfortunately, when pushed through a cold, geared, brush motor, actual output power might be less than 2AH. (The AH rating of SLA batteries is typically determined by a slow drain, over a 20 hr period, with a more typical 1 hr drain, output is approximately only 60% of "rated".)
Why even bother?
I bought my first about 3 years ago, when gas passed $4/gallon.
A complete electric vehicle for less than $400, which almost covered my, run around town, "errand", gas cost, for that summer!
$348 w/shipping included, available, right now from Amazon.com and Walmart.com!
Of course I had to upgrade capability and capacity! Speed was increased from OEM 15mph to, variously, 20, 22, 24, and 27mph, (motor alone speed), using various methods. "Motor only" range was about 8 miles, increased to, 40 miles @ 16mph, (30 miles @ 20 mph). Of course I upgraded pedal assist capability to allow much better range, and higher speed.
However, I digress.
My main point is that I built Li-ion battery packs, from used notebook batteries! EZip OEM batteries are 24v SLA batteries with a usable 6AH. I built 25.9v 31.2AH packs, as well as 37v 20.8AH. Approximately 5X the usable output, at about 60% of the weight. For the Winter, I place the packs in insulated, fabric "lunch bags" with cardboard inserts, allowing for insertion into the OEM battery racks. The bottom power contacts were impractical, so I converted to AC power cord connectors. So, battery is kept warm, and dry, by insulated bag. Removal to a warm location is a simple, unplug and lift, by built in lunch bag, handle.
Bag is secured by a cable lock that happened to fit perfectly around rear rack, and over top of pack.
Yes, I do ride in Winter! Studded tires are essential. Visibility and proper attire, are important factors in being, "safe & warm".
This Winters project, will be, a Schwinn 3-wheeler conversion, to electric assist. Canopy and windshield are definite possibilities.
I am making progress towards an eCar!
Stories of my upgrades and adventures will be posted in the ebike section.
I will post notification here, when completed, (I have many pictures and articles posted on other sites, that use an incompatible format, proper translation might take some little work).
EZIP ENGINEERING 101