Is there a way to check this before killing a light?

[RaceR86]

Unless you know the driver is rated for higher voltage than 4,3V. Do not use two li-ion batteries on it.

Here you can see what kind of amps (and voltage) all the common emitters can be run at.

Cree, Luminus, Seoul Semiconductor, and Nichia LED comparison

I would suggest reading my guide on tint, binning, and CRI before reading this. This is a comparison between all of the common LEDs. The LEDs included are: XP-G, XP-G2, XM-L, XM-L2, XR-E, XP-E, XP-E2, Nichia 219, SSC-P7, MC-E, SST-50, SST-90, MT-G2 XP-G The XP-G is a small Cree LED that is 3.45 mm by 3.45mm. The size of the die is 1.4mm by 1.4mm for a total die surface of 1.96mm2 which is often simplified to 2mm2. It is distinguishable by it's size and the grid of 4 strips. [image] It has…

Copper mounted emitters results are found here.