Why does my iPhone stop and start charging every few seconds?

First, use a flashlight and see if there is any debris or lint within the charging port, and if so, use a wooden or plastic toothpick to carefully get it all out, but not metal.

Second, are you using an Apple or MFi certified charging cable? You should be, and try using a different cable and outlet.

Please review for more info: If your iPhone or iPod touch won't charge - Apple Support

It won't hurt to check for lint or dust, but it probably won't help either.

Lint or dust or whatever would prevent the battery from charging at all, or it might allow the battery to charge if you wiggled and held the cable in just the right way. Things would be very inconsistent.

But, lint or dust would rarely be a cause for the charging stopping and starting on a very regular basis every few seconds. That is almost always either a battery or board issue.....and a trip to the Genius Bar or authorized Apple service shop.

You can find a list of authorized shops in your area using this link: Find Locations

If the charger is not working, try flipping it around. Otherwise I would recommend trying a different charger. If that doesn’t work, try a different plug nearby

What is your Battery Heath at Settings > Battery > Battery Health & Charging > Maximum Capacity?

Nifty71 wrote:

100%

That would indicate a newly installed battery from somewhere or brand new phone just purchased. What is the history of the device?

Hello~ What model iPhone? Is this the original battery? Have you had the battery changed by a third party repair shop?

~Katana-San~

We assume that you are using a power supply and cable, correct?

Or, are you trying to charge using wireless?

Hello~ Where did you buy that iPhone? No iPhone 15 that has been used for any length of time will have a battery health of 100%.

~Katana-San~