Just wondered how you got on after finding your post, as I could do with some advice too.
I've been using the EMS Analyser software, BMS Monitor & Battery Wizard software that a kind guy on YouTube sent me.
When we bought our Gwiz a year ago (we bought it quite reasonably), it had no history, and the commercial seller could not guarantee the state of the batteries. We only use it for short distances, school runs etc, so its been great for a year, and gave us between 20-30 miles range.
During this time I've kept the batteries topped up, but after a year we're starting to have some issues.
So I'm now trying to decipher the exact age of the batteries from the log files from the car. The car has now done 18,666 miles to date. I'm guessing this means it must have had a few sets of batteries in its time. My question is this - does anyone know if the number of "cycles" (e.g. recharges) is reset upon a new set of batteries being installed, and also what to watch out for when looking through the system data spreadsheet to try and work out if the batteries need replacing?
From what I can see T125's have an approximate lifespan of 650 cycles, our Gwiz is on 600 by the looks of the data, and recently the car's SOC meter started swinging up and down to zero upon accellerating hard at 50% charge level, even though we charged it fully the night before, this happened after about 6 miles of driving.
Obviously this worried me, I immediately plugged in the BMS software and studied the error (a >0.7 voltage warning), and low and behold, we had a voltage of 5.4 Volts on one battery. Two others were under 6 volts and the others were at approx 6.5 volts.
I realised that this could be evidence of some batteries giving up, but then wondered if it needed equalizing, so I've equalized and all seems well, but after visually inspecting the cells today I did notice there is some white sulphation visible between the plates, this seems consistent on each battery, although looking at the logs it did confirm my thoughts re the lower voltage.
I'm presuming given the 600 cycles a whole new set would be in order

Should we run this set into the ground? Or change them now - I'm presuming the range will start to drop quite rapidly towards the end of their life.
On that subject anyone know what terminal type you need? is it EHPT?