Accented character issue in path on batch file

Hello,
I have a problem with a batch script I created.
My script is meant to run a query and generate an Excel file in a specific location, but the folder in question has an accent, and I'm unable to save it; I get an error message: "Spool file creation impossible "D:\système\...\monfichier.csv"

Here is an excerpt from my script

set echo off
set newp none
set termout off
set feedb off
set head on
set heads on
set underline off
set lines 10000
set pagesize 32000
set colsep ";"
define date1=foo
column champ format a28
......
select 'monfichier_au_'||to_char(sysdate,'dd_mm_yyyy')||'.csv' date1 from dual;
set termout on
spool "D:\système\&date1"
.....

I have tried several solutions such as:
chcp 28591 > null
or
set NLS_LANG=FRENCH_FRANCE.WE8PC850

but nothing works

Could you please tell me which command line to use to take accents into account? I'm using quotes, so I don't know what to do.

I have tested saving in a folder without special characters, and I do not have the problem.

Thank you very much for your help

Configuration: Windows / Firefox 72.0