It is not only the wrong one, but it can be deadly. If you look at the label. it states the black is common for the input and output. The The above converter is a cheap offshore model, and you actually want a higher voltage input rating, and a 13 - 14 Volt DC output.
As far as the dangerous part, the Think battery pack ISOLATED (+ and - NOT connected to the Think chassis, or ‘frame’). The 13 Volt DC negative lead is grounded to the frame (Notable is that just about every motor vehicle sold in North America in the last 50 years is 12 Volt Negative Ground)…
The lightning bolt icon on the cluster is a safety warning that there is voltage present from the battery pack to the frame… A warning for safety).
You do not need a functioning DC/DC converter (but it must not be internally shorted from input to output, though, to power up and drive. That’s what caused the Think that caught fire and burned up, as posted on my website). Not to be unexpected, since hooking up a 72 Volt battery pack to your automobile 12 Volt battery would do the same. A failed DC/DC converter will not have any 12 Volt items operational. The cluster back-light is fed from the converter, so it will not light up, either.
Electrons In Motion LLC