The D1 Mini has a regulator built in. It does exactly what your external "stabilizer" does, but it performs better. It seems you do not understand what an AMS1117 is. It's just a voltage regulator, and it requires some headroom to work properly. At 3.5V, the AMS1117 would probably have cut out long before that.
There is absolutely no point in buying an AMS1117 regulator. Connect the battery to the 5V pin, and save your money.