I used to be a fan of magnets & scared to solder blob the cell positive anodes.
However after getting a reasonable soldering station to replace my aged non temperature controlled 40 watt iron & gaining a lot more practice (& proficiency) at soldering I solder blobbed a few cells with no problems.
Then when doing some tail cap amp readings I noticed that 2 cells with a magnet for a button in series gave around 0.5A less than the same cells without a magnet when tested in the same light.
I took the cell with a magnet, took the magnet off & soldered a blob on & got about 0.5A higher reading than with the magnet.
This makes me think that the magnets I was using have a fair amount of resistance.
Now I don"t know if all magnets are the same, or if just mine are high resistance, but a combination of that & the fact that I now feel comfortable with solder blobbing cells means that I won"t go back to magnets (unless it was an emergency).
The other option if you don"t feel comfortable solder blobbing is to use one of these purpose made Jaxman cell connectors
https://www.aliexpress.com/item/Con...lt&btsid=a2471e9e-91bb-487d-81d7-bd18affe490a
They are available in 2 sizes for both 18650 & 26650 cells, although when I bought mine there were only the 18650 ones which I used with 26650"s fine so I think either would work fine with 26500"s.