Dynamically converting a list of Excel files to csv files in R

You can try this using rio, since it seems like that's what you're already using:

library("rio")
xls <- dir(pattern = "xlsx")
created <- mapply(convert, xls, gsub("xlsx", "csv", xls))
unlink(xls) # delete xlsx files

library(readxl)

# Create a vector of Excel files to read
files.to.read = list.files(pattern="xlsx")

# Read each file and write it to csv
lapply(files.to.read, function(f) {
  df = read_excel(f, sheet=1)
  write.csv(df, gsub("xlsx", "csv", f), row.names=FALSE)
})

You can remove the files with the command below. However, this is dangerous to run automatically right after the previous code. If the previous code fails for some reason, the code below will still delete your Excel files.

lapply(files.to.read, file.remove)

You could wrap it in a try/catch block to be safe.