Even on flat ground, I sag a decent bit and on slight up hills, I sag pretty bad. I have very little flat ground anywheres to ride on. San Francisco in the sunset district is almost exclusively hills. Probably under 10% of the roads here are flat or under 2% grade of steepness. This means I’m always sagging pretty heavily. So when I get my cells down to 3.6v, I must stop. If I have steeper hills to tackle, I must tackle them before I hit 3.8v or I’ll sag down past 3.2v per cell. In effect, I’m losing about 30% of my range due to sag. Now with high discharge lipos, I can get my cells down to 3.3v before I sag before the cutoff. The effect is most range. I know I’m over simplifying this, but my real world tests with lipos and with liion showed me that a 12s 10 Ah li-ion got 6 miles of range while a 12s 8 Ah lipo got 8 miles of range. This is one of the reasons why I nag so much about sag. It slightly dampens performance (which may not be a big deal to some, it should be if your buying the quote un quote “most powerful” direct drive board IMO), but also reduces range, as you must stop at a higher voltage. With the VESC, this will just mean I can’t climb the hills I need to climb when my battery is suppose to have 50% left, as my voltage cutoff will start to kickin. Even with 25% of my lipo left, I can climb the hills I need to without sagging below 3.2.
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