Just for giggles, I opened up the battery compartment on my brand new GBA SP 2.0 units today... and was surprised...
The new GBA with "brighter" screen actually has a SMALLER CAPACITY battery under the hood.
The new model battery is 3.8V, 600mA.
The old model was 3.8V, 700mA.
More milliamps means more capacity, which translates directly into more play time.
So, if you have an old SP laying around, swap the batteries and you'll gain a bit of extra play. And if you're lucky enough to have one of the 1000mA batteries that is only sold in Japan, I envy you.
The new GBA with "brighter" screen actually has a SMALLER CAPACITY battery under the hood.
The new model battery is 3.8V, 600mA.
The old model was 3.8V, 700mA.
More milliamps means more capacity, which translates directly into more play time.
So, if you have an old SP laying around, swap the batteries and you'll gain a bit of extra play. And if you're lucky enough to have one of the 1000mA batteries that is only sold in Japan, I envy you.