High power IR transmitter circuit for ESP8266
These are rated probably much higher than yours.

> SFH 4550 1.1W/sr @100mA +/-3 deg $0.70 approx.

Three should drop 4.5V typ 4.8V max allowing 0.2-0.5 Vce drop with base current of 10mA The 2N3904 is not a great choice. It will have Vbe=1.5V @Ib=10mA so consider a better NPN. Even PN2222 is marginal.

Using a PN2222 Vbe=1.3V max @Ib=15mA Rbe~40 Ohms above0.7V


I calculated this way. Assuming driver Rout=50, Rbe=40 above 0.7V
using (5-0.7)V/10mA= 430 Ohms then subtract {Rout+Rbe} Ohms allowance for CMOS driver and bulk VBE resistance giving Rb=430-90=340 Ohms 
with Vce(sat) for PN2222 =0.4max @150mA or PN2222A=0.3Vmax @150mA
this gives some tolerance on Ic with variance on LED and Vce drops, so adding &lt;=1 Ohm to emitter allows you to measure If.