A:AnswerYes but you will have to do some semi risky disassembly. The battery is completely and fully replaceable but you need to take the speaker apart (although being very simple it is still semi risky) pro tip = follow every step thoroughly. If you do that is is completely harmless to the speaker.
A:AnswerSadly no. THe jbl flip 4 has the more widely used (jbl connect +) as the jbl flip 5 has the more new (Jbl party boost) and they are not inter-compatible
A:AnswerCheck out the detailed comparison on our JBL Flip 4 and Flip 5 here:
https://www.jbl.com/compare?cid=bluetooth-speakers&pid1=JBLFLIP5BLUAM&pid2=JBLFLIP4BLKAM
A:AnswerYou can on the jbl flip 4, but they removed that feature on the jbl flip 5 (they sound basically the same, the only downfall of the flip 4 in my opinion is that is t charges with micro b instead of usb-c, so it charges slower, but its not that big of a difference) so if you want the jbl flip 4 ($80-100) go over to amazon and get it