[pshute]

I notice that the 9900 has a slightly different battery compared to the 9700 and 9000 series. The new JM1 battery is obviously thinner and has a bit less capacity than the old M-S1, but is very close to the same length and width, and the contacts are almost in the same place.

Would it be safe to charge a JM1 in a battery charger we bought for M-S1 batteries? Has anyone tried this? Note that I'm talking about a standalone battery charger, not something that plugs into the phone.

I assume the phone chargers are interchangeable apart from the micro/mini USB issue.

[stevew]

If it makes contact, it will be fine...the charger charges by sensing load and capacity on the battery, and adjusts for any battery that it charges. Charge voltage is the same for both batteries, but the MS-1 battery is higher capacity (ma). You should have no issue, if the charger fits and the battery contacts stay tightly contacted to the charger.