This may not be altogether the case. Lithium battery cells chemically tire under load and when rested they recover charge. Some of eZee's most powerful models have shown this very clearly, hill climbing dropping the meter indication and sometimes a low voltage cut-out occurring. Pausing then for a few minutes allows the battery to recover and the meter indication to improve, which is the same as going downhill with the motor no longer driving.I share Seataltea's view that rolling downhill charges the battery on the Mistral. Often I have been down to three lights, rolled down a long hill and immediately got up to four lights and even five. There is clearly some charging going on because when the bike is wheeled along one LED definitely lights and remains lit for as long as you are moving.
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