HP-41CX how to deal with NiHM

[Giuseppe Marullo]

Hi all,
I did my homework and I was able to open a broken rechargeable battery pack (with good advices here and there from others, thanks).
A friend pointed me to a site where they sell replacement batteries, but unluckly they are NiHM, not NiCd.

How to deal with them? I know they are a little problematic when swapped with existing NiCd circuitry-aware.
Especially overcharging them is risky. I know that they are not charged too fast, but I am sort of a "What? Can't believe I left the battrey charging the whole weekend" user.

Any suggestion? I got also N 220mA/h NiCd batteries, but they won't fit with the circuit, to use them I should use a very thin/tiny circuit and use a different AC connector.
TIA,

Giuseppe Marullo