Lithium batteries in cold weather

At the beginning of every riding season, we tend to get lots of phone calls with people asking very similar questions- about using lithium motorcycle batteries in cold weather.

This makes sense, as in much of the US the grip of winter is starting to loosen, prompting people to start to consider riding their motorcycles. For a lightweight motorcycle battery company this means lots of people are replacing batteries, or trying to figure out what happened to the batteries they have.

The first common phone call goes something like this:
Rider: “Hi- I just went out to the garage to ride my bike, and my battery was dead. Why is my battery dead?”
FSP: “When did you notice that the battery was not working? What is the battery voltage?”
Rider: “Today, when I tried to start it. It worked great last season, but now its dead. I dont know what the voltage is- how do I measure that?”
FSP: “You measure voltage with a multi-meter. Did you leave the battery connected to your bike all winter without riding?”
Rider: “Yes. I didnt even ride once. Too much snow.”
FSP: “Well, it sounds like your bike drained the battery over the winter. You know that even when your bike is off, it still requires power. That is why we always talk about using a Pacemaker or similar charger to keep the battery in good state of charge.”

The problem here is that people assume that you can walk away from your bike and battery for 4-5 months, and when you come back everything will be fine.

That isnt the case unfortunately- tires lose air, fuel turns nasty, and batteries get drained.

The second call has to do with using lithium motorcycle batteries in cold weather.

It is 45 degrees outside, and has been in the 30′s for months. Your battery is basically frozen. You turn on the key and…nothing. WTH?
Well, the lithium that we use in our Pulse motorcycle batteries- A123 Systems LiFeP04 Nanophosphate®- tends to go dormant at cold temperatures. Our batteries will require a minute or two of “waking them up” before they will start your bike.

You can do this a few ways:
1. Turn on the headlights for a few minutes- until they are bright
2. Hold the horn button for a few minutes- until it sounds normal
3. Cycle the fuel pump 10-15 times, until it sounds normal

You should then be able to start your bike.

Note: I have seen videos from other battery companies where they will try to start a bike to wake up a battery. We do not recommend this at all. You could easily damage the starter, starter gear, sprag, and other components. It is much safer to just try to other methods I recommend above.

Bottom line- lithium motorcycle batteries work great in cold weather, provided you give them the proper wake up sequence. If you are looking for a battery that will work in freezing temps without having to deal with waiting a minute or two, lithium may not be for you. Unfortunately, this is one of the limitations of lithium batteries as they currently exist.

At Full Spectrum Power, we believe it is a small trade-off to make for light weight, high power, and small size- but that is a decision you need to make for yourself. Lithium batteries are not always the best choice, for every motorcycle, rider, and application. Sometimes- many times- lead acid or AGM is a better choice.


Jason Levitt
Jason Levitt

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