I think the problem with those free api is that you might even get blocked doing 100 requests in less than a minute.
I made this javascript tool which allows you to do search for address balances, but it can't handle 100 addresses (I even used a try/catch method with a seocnd api when you get to api request limits)
Take a look
https://bitcoindata.science/bitcoin-balance-checkHi i want to check a bulk addresses balance, actually i use request.get in python way with blockstream but it's too slow (around 100 addresses in 46 seconds)
Why people always want to do this? It is always slow.
The correct way to do this faster is download an updated list of address with balance
List of all Bitcoin addresses with a balance Then load that file into a database/bloom filter or some other custom method.
Check your list against that method.
WIth this way you can be able to check million of address in less than a second
This is not faster than 46 seconds (as you have to download a huge file)... and the data might not be updated.