There is a lot of great info in this thread, but also... Sadly there is a LOT of misinformation as well
I need to clarify about the power tank stuff. DIGINOW CHARGERS WORK GREAT WITH POWER TANKS.
The issues being described by Shattow are not related to cell mismatch either. There is an issue with stock Zeros and power tanks when the bikes are at a low SOC. If you turn the bike off without charging the power tank will come on first and not let the bike go. I explainerd this quite clearly to Shattow when he got his power tank. I explained it EXTRA CLEARLY because he has the latest firmware which I think exacerbates the issue due to amp hour miscalculation. But I am not sure on that yet.
I just tested Shattows bike which has a 2.8kw powertank and 9.9kw of charging and followed the basic best practices of having a power tank and everything worked great. 130 miles of testing and super charging.
The basic rules of having a power tank no matter WHAT type of charger you have is to not turn the bike off at a low SOC without charging or without being near a charger, and this is unrelated to if your power tank matches your battery or your charger type.
Now all that said, what Shattow did not mention was that he has a force charge algorithem in his control board which does not give the power tank time to initialize if it gets into some wonky state. So... he is down here to get a production board on his bike.
So please don't let this misinformation prevent you from getting the best possible setup for a Zero, 3 in the pan and a power tank. This is my new personal setup as well. I just rode from LA to Monterey in 8 hours with this setup with a mismatched battery and power tank 2014 PT and 2017 battery, and it worked great. I also have the old firmware.
If anyone has questions please ask me, it's what I'm here for. I know my product, I know Zero Motorcycles and I have a VERY strong interest in making the best products for them.