Can the iPhone 6 operate if there is no bettery insatlled

Hello @owen_the_techie,

You cannot get your iPhone to start if it does not have a battery installed.

However, if you have a charged battery connected, and you turn on your iPhone 6, THEN remove the battery, it will stay ON provided the charging cable and cube or good quality and provide enough power.

But, I bet that it will very soon start boot-looping because the battery does not only provide power to the iPhone; it also sends charge level info and temperature info. When those are missing, specially gas gauge (charge level), the iPhone is likely to start boot-looping. Furthermore too much boot-looping and gas gauge error reporting can corrupt your data partition that only a wipe and restore can repair.