Battery Performance in the Cold

[RoadieRoger]

Did 24 miles on the Batribike Quartz today with the temperature reading 3C . On the same route when new 18 months ago, I managed 33 miles and last Autumn 27 miles . My machine is kept in a cold shed and was recharged fully about 2 weeks ago and hadn`t been ridden until today . During this time the temperature has been down as low as -6C several times . Unlike some riders I like to see my red handlebar LED`s,as when I get down to one I know that the power might run out. This happened today and after selecting Low Assist it got me home the last mile . The red lights on top of the battery are no guide, as 3 were still lit when I arrived back . A charge of 4 hours usually gives me a green on the charger unit , the battery is an 8Ah . When purchasing an E Bike this lower battery capacity might be satisfactory initially for the mileage , but degradation over time reduces this distance .The 10Ah would be the minimum in my view , balancing replacement cost against Range .
For the Aircraft Spotters amongst us , I stopped at Cardiff Airport on my ride to watch an IL 76 Freighter of SilkWay Airlines of Azerbaijan starting up to return to Baku .The 4K-AZ Country Code of the Aircraft`s Registration had me stumped at first . That`s the beauty of the Ebike you can park on the pavement or verge , do it on the Moped and you are likely to be moved on .

 

[NRG]

Letting the battery 'freeze' is not a good idea for a long healthy life...

 

[Synthman]

I keep the battery in the house. When it was really cold (below 0°c) I would place the battery on top of a storage heater for a few minutes to warm it up a bit before I set off. This method really seemed to work, as the majority of my journeys are 15 mins or less.

I've definitely noticed a 10-20% drop in range and performance since I got it 2 years ago. I can still get 10 miles from the battery, but it does have a tendancy to cut out when the throttle has been opened for a while. If I run the bike with reduced throttle or stop for a couple of minutes the battery does recover strength a bit.

I haven't felt much reduction in performance in the cold, the difference between riding in 6°c and -2°c wasn't really noticeable. But in the summer the bike pulls harder, has a higher top speed and more range.

I keep an eye on the battery meter (I believe its more accurate than on other e-bikes, and it has 5 LEDs) and it does drop on inclines quite a bit now. A year ago it didn't do that. But at least when the last LED is lit (low warning) I can tell that the battery will shut off unless I reduce throttle. So I reduce power slightly until the next LED lights. If it does cut out, I have to stop the bike, remove the key, open the seat, and disconnect and reconnect the power cable!

When the weather warms up to 17°c or more only then will I be able to truly judge if the battery needs replacing. But it was manufactured in 2007, and has done 338 charges and about 3250 miles.