Low battery warning failed me.

  • I usually do not tempt fate, as I don't want to walk with the OW.
    Today however I managed to forget all my stuff at work, and had to go back.
    It's cold, my tire is soft, and the charge didn't quite make it.
    Not really a problem, since it was close enough anyway, but...
    It failed to do a low battery pushback warning, and just died on me.
    A long time since I had to outrun the board, but my reflexes didn't fail me (saved me twice today actually).

    I wonder if it's a bug, or something related to where the limit is versus the amount drained. Say if the battery drains too fast, so that it doesn't have time to react. or I don't know...

    As I said, I almost never push it when it comes to range, but did so twice recently. This time, and a week or so ago when I was SURE that I had recharged it (I really hadn't),
    Last time however I did get the pushback warning, and everything was fine.

    I'm really not going anywhere with this post. Just, stay safe!

    I'm riding the old E 2.0 (or extreme 2000)
    Since I don't have an apple device and simply love it.

  • The root cause might be quite simple. It is my guess only but:

    LIFEPO4 batteries have nasty discharge curve. Voltage remains almost the same when discharging. It makes it difficult to estimate charge percentage based on voltage. So they might decide to count mAh which you used. Unfortunately in lower temperatures battery capacity drops. Result might be as you observed.

  • @Kwok I was thinking along the lines of that yes. Some reading up on the topic reveals a few different methods of measurement that aren't pure voltage based (which is hard to do on Lithium batteries).
    Still, it would have been interesting to know what % the board thought that it was at when failing.

    Just to make sure, I restarted it. Power button indicated low power. Rode it slowly for a few seconds, and the board died again. Definitely dead battery.
    Charged it at work and rode home 30 min later, no problem.

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