To get wider bars, you need to change your query and aggregate your data over a longer period. It is not just a cosmetic change so you cannot change the width like you want to otherwise you would change the meaning of the data.
If you want to aggregate in 10 minute intervals, then in InfluxDB (I’m guessing that is the db you are using) change the Group by time interval to a larger value. In the example below, the data is grouped in 10 minute intervals and the Group by time interval field is set to >10m. You can read more about it in the help text found by clicking on the group by time info button under the field.
