My experiments pretty much proved that the following would happen: a) Leave batteries in overnight - handset display says they're full. b) Pull batteries out momentarily & put them back in c) Now handset display says (the same batteries) need 7 hours of charging
So, I'm going with the recommendation to ignore whatever the handset display says if you've just put in batteries.
Hmmm, Panasonic implemented mandatory >7 hour initial charge to ensure long battery life. On any rechargeable batteries proper initial charge is very important. It is not whether battery is charged or not. It is just so. You are obliged to make sure at least 7 hour charging time. Usually owners manual does not explain things in full. Panasonic CL phones in my house is almost 10 years old. None yet needs new battery.
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