does anyone know if i can use a xb1x/s battery pack in a xbox one controller ok

Should be noted also if battery packs are fine if you are using third party HOWEVER the ones with the charging backplate won't work becauae of the differences in plates.

Only battery packs will work or updated kits I got one with 2 backs but it's depending on the third party what is included

if you are on about the official play n charge kit then i am using an xbox one version in the series controller, the only difference is obviously the charging cable.

Does anyone know if one can recharge rechargeable batteries via the controller?

If they can, then that's the route I will use.

But then if it;s the wrong battery pack, it shoudn't work with either controller ...the fact it works in one but not the other points to an issue with the second controller

The Xbox One Venom battery pack won't even fit in the Series X controller (or at least not without trimming bits off it)..as the OP can fit the pack with no issue, it suggests it's the right battery pack. Unless Venom have released more than one battery pack for the Series X?

The Series X controllers available now uses the same official battery packs as the Xbox One and Series S controllers.