解决方法

将openpyxl定义的非法字符用空字符代替，具体方法如下

from openpyxl.cell.cell import ILLEGAL_CHARACTERS_RE
import openpyxl
import re

# 写入之前，先将非法字符用空格代替
content = ILLEGAL_CHARACTERS_RE.sub(r'', content)
ws.cell(ridx, cidx).value = content

参考

1. https://blog.csdn.net/javajiawei/article/details/97147219