Battery warmer

[maraetsky]

Happy holidays everyone!

In the cold weather I have been keeping my ODK in a small warm room in our barn, but it is crowded. I would prefer to keep the bike in the garage, which would be more spacious and convenient. Would it be good to use a battery warmer on the ODK battery? Any recommendations for what to buy?

BTW, did you get any cool bike accessory presents?

 

[Nirmala]

Is the battery removable? I bring the batteries from our Magnum Ui5's inside while leaving the bike itself in the garage.

 

[maraetsky]

The ODK batteries are not removable. I don't know why that is the case, when it would make things so much easier. (If it's a theft issue, I would think there would be a way to add a slot or other feature to the battery that would allow it to have a lockable cable threaded through it.)

 

[Jim W]

Happy holidays everyone!

In the cold weather I have been keeping my ODK in a small warm room in our barn, but it is crowded. I would prefer to keep the bike in the garage, which would be more spacious and convenient. Would it be good to use a battery warmer on the ODK battery? Any recommendations for what to buy?

BTW, did you get any cool bike accessory presents?

Hi Maraetsky,

I'm glad I don't have to worry about that kind of issue. Unfortunately I can't give any definitive advice on your question; however, if I had to store my bike for three or four months, rather than buy a battery warmer, I'd just unscrew the battery from the frame and store it inside my house. There are only four screws you have to remove. But then again, I don't know how disconnecting the battery would affect your Cycle Analyzer, if you have one attached. Why don't you e-mail Tora at Juiced Riders: [email protected].

 

[maraetsky]

Hi Jim,

I'd like to keep riding on some days when it's above freezing, but the temps could drop a lot at night, which wouldn't be good for the battery unless it is protected. I'll write to Tora and ask about options. Thanks!

I'm jealous of your lovely warmer climate, but we have had a very pleasant fall and winter up until now. A first snowstorm is predicted for tomorrow in the Northeast. This will be the first winter in a long time that I don't have to commute to work, and I love it.

 

[maraetsky]

I am happy to report Tora's response to my question about keeping the battery safe in cold weather:

"The battery does not need to be kept warm necessarily even when charging. It is just that there will be noticeable temporary decrease in range when the pack is in colder conditions.

It restores when you get back to warmer conditions."

 

[JoePah]

That is poorly worded advice... Never charge any lithium battery when the pack is less than 40F, unless you can dial down the charging rate significantly.

Never charge any battery below freezing.

There are several threads on this subject, based on Battery university and vendor recommendations.

 

[Tora Harris]

Our pack's battery management system is designed to reject a charge if it gets too cold. Also we set the stock charger so it does not attempt to charge the pack all the way up. The best thing is if you have a Cycle Satiator Programable charger and use the 80% setting in the lower temperatures if you must charge. Frequent cold weather charging can reduce the charge cycles compared to moderate temps, but infrequent use should not be a huge problem. It is an area that needs some improvement when it comes to battery technology.

 

[maraetsky]

JoePah, thanks for writing. I will look for the threads you mentioned.

Tora, the additional information is appreciated. I ordered a Cycle Satiator today.

 

[Tara D.]

@maraetsky I'm glad you got answers to your questions! As far as bike accessory presents- Not really but I did get these earrings haha close enough for me. Happy new year!

 

[maraetsky]

Happy new year, Tara! The new earrings are very cool accessories!

 

[Patrick D.]

One of the problems with charging below freezing is voltage drift. At 100% full charge your cell voltage will be 4.2v. As the temperature rises above freezing so will your voltage pushing the cells over 4.2v and damaging them. Overcharged cells can catch on fire. The other problem is the internal resistance. As temps go down resistance goes up making the cells less capable of taking a normal charge rate. Luckily most ebike chargers only put out 3-7a so it should not be a problem. If you cant afford the Cycle Satiator charger than get a Lunacycle charger with the 80/90/100% switch. Charge to 90% most of the time. Once a month charge to 100% to allow your BMS to balance each parallel string.