Bad news for the Kobo battery.
I was looking into Kobo as a viable reader and when I asked questions about battery replacement, I was told there is no option for this and Kobo will not replace the battery. She said that you are expected to throw it away and buy a new one every 3 years.
I guess you could just figure it is like a set of tires, but even Amazon will replace your Kindle battery for $60. Maybe I am getting old, but the idea of so many battery powered gadgets with a 3 year life until it is trashed just seems wrong.