What does the output of model.predict function from Keras mean?
The output of a neural network will never, by default, be binary - i.e. zeros or ones. The network works with continuous values (not discrete) in order to optimise the loss more freely in the framework of gradient descent.

Have a look here at a similar question that also shows some code. 

Without any kind of tweaking and scaling, the output of your network is likely to fall somewhere in the range of your input, in terms of its nominal value. In your case, that seems to be roughly between 0 and 2.

You could now write a function that turns your values above into 0 or 1, based on some threshold. For example, scale the values to be in the range [0, 1], then if the value is below 0.5, return 0, if above 0.5, return 1.