What are some technical innovations to fight climate change?

There are no silver bullets.

The smart grid does nothing to encourage use of renewable energy. It just offers the possibility of creating a large spot market for electrical energy, where many buyers and sellers can compete. Tax policies and other incentives could alter the energy mix for sure but the grid by itself is just a tool.

There is one key technology that can have a huge impact: A breakthrough in storage (batteries, supercapacitors) that would permit the average building or neighborhood to meet peak demand without stressing the utility, storing energy when sun & wind is available and consuming it when it's not.

This kind of breakthrough would also kill the gasoline-powered car.

Nuclear fusion is a big one. It would provide virtually unlimited energy with zero emissions, and, I believe, be much safer than current fission technology.

An abundance of energy would also help solve other problems, such as drinking water, since we could use this cheap energy to run desalination plants.

Of course, the catch is no one is really sure if the technology is even possible.

Concentrated solar thermal power with storage could be big, because it's projected to be able to deliver renewable energy at under 10 cents per kWh in the next decade, and could provide baseload power.

I also agree that battery technology could be a huge gamechanger and make the internal combustion engine obsolete.

Carbon sequestration technologies will be helpful, especially if used in conjunction with biomass energy.  This scheme would be carbon negative. 

Secondly, advances in automation can change the economics of manufacturing.  Increased automation reduces labor costs so transport costs become more significant.  This favors factories located near markets in North America and Europe.  With less demand for energy to run export driven factories, China will build fewer coal plants and have time to focus on developing cleaner energy. 

Why fight a non-existant foe.Make love not war.

According to this article

http://techon.nikkeibp.co.jp/english/NEWS_EN/20090225/166270/

Li-Air battery technology looks far more promising than Li-Ion, especially for automotive applications.