Background: I've been experimenting with different voltages on my rear hub motor ebike, by running different combinations of lipos in series with my 14S UPP triangle pack (cheap cells), mainly for deciding on my future battery upgrade. My main pack is limited to 30A continuous, so I've limited battery current to 30A to avoid abusing it too much. I've gone as high as 22S (90V), which was fun, but not what I'm looking for for my main pack. I'm landing at 18S as being a good combination for my riding, giving decent speed with field weakening, on my slow wind motor, to keep up with traffic when needed (something over 30mph, but haven't tested the top speed). It also climbs better, since I can maintain a higher speed too. I did two 1 mile climbs in a row the other day, 800 ft elevation so around 15%, and the motor was barely warm.
I've started to come full circle with respect to my main pack replacement. When I started this endeavor, someone on this forum suggested that I just keep 14S and upgrade the cells, so I'm starting to see the light. I have a feeling that the extra lipos/voltage are helping with my performance due to the extra power provided at the same 30A current limit, and that if my main pack had greater current capability, I could replicate the same performance (climbing), with 14S. I don't really need the extra speed, although fun to play with, for my normal riding, but having the extra current on tap makes a difference. So, I'm going to do a couple more tests to see.
I want to use the same hard cased UPP pack style for the upgrade, and 14S seems to provide space for the most parallel groups (8P). Going to 16S would have the same cell count, but fewer parallel groups, and 13S wouldn't allow anything greater than 8P either. UPP has a 14S8P option using Sanyo cells and a 40A BMS, 100A peak.
Question: So here's the question: If I use my CA to limit current to 40A, and connect lipos for 14S (no main pack), will that provide a good proxy for 14S performance of a battery pack with quality 18650 cells?
I'm going to still be using my series lipos for fun, but my main goal when starting my experiments is to find the best voltage and cell combination before I commit to the upgrade.
I've started to come full circle with respect to my main pack replacement. When I started this endeavor, someone on this forum suggested that I just keep 14S and upgrade the cells, so I'm starting to see the light. I have a feeling that the extra lipos/voltage are helping with my performance due to the extra power provided at the same 30A current limit, and that if my main pack had greater current capability, I could replicate the same performance (climbing), with 14S. I don't really need the extra speed, although fun to play with, for my normal riding, but having the extra current on tap makes a difference. So, I'm going to do a couple more tests to see.
I want to use the same hard cased UPP pack style for the upgrade, and 14S seems to provide space for the most parallel groups (8P). Going to 16S would have the same cell count, but fewer parallel groups, and 13S wouldn't allow anything greater than 8P either. UPP has a 14S8P option using Sanyo cells and a 40A BMS, 100A peak.
Question: So here's the question: If I use my CA to limit current to 40A, and connect lipos for 14S (no main pack), will that provide a good proxy for 14S performance of a battery pack with quality 18650 cells?
I'm going to still be using my series lipos for fun, but my main goal when starting my experiments is to find the best voltage and cell combination before I commit to the upgrade.