Take a gander at that! Why does it need so many solar panels? Reminds me of another story about china recently:
I don’t see any technical reasons why Hauwei towers couldn’t be transmitting to the balloon. Subsequently, the balloon could transmit to satellite, since the payload has enough solar panels to power a high gain transmitter. This technique could be used to exfiltrate secret military data. Is this the case? It’s hard to say. My guess is the balloon fulfills several objectives for the Chinese, and this is just one of them.