Is God Darkness or Light? - 1 Timothy 6:16; 1 Kings 8:12; Psalm 18:11; 97:2

1 Timothy 6:16 [Jesus Christ], who alone is immortal and who lives in unapproachable light, whom no one has seen or can see. To him be honor and might forever. Amen.

1 Kings 8:12 Then Solomon said, "The Lord has said that he would dwell in a dark cloud."

Psalm 18:11 He made darkness his covering, his canopy around him - the dark rain clouds of the sky.

Psalm 97:2 Clouds and thick darkness surround him; righteousness and justice are the foundation of his throne.

The terms "light" and "darkness" can both be used of God without being contradictory. They are are actually complimentary. Understanding their context is key, so let's look at the verses you mentioned.

In 1 Timothy 6:16, Paul speaks of God's unapproachability (Ex. 24:17; 34:35; Ps. 104:2). God is light (1 John 1:5; cf. John 1:4). Without special equipment we do not look directly into the light of the sun because it is too bright. As one of my former seminary professors stated, "We need it to see by, yet we cannot look into it, for it is too intensely brilliant." So in this sense, God dwells in unapproachable light. Also, a nuance of light being so brilliant is that it is then unsearchable - and so God seems "dark" to us (Rom. 11:33).

1 Kings 8:12 references Psalm 18:11 and 97:2 and speaks of God manifesting himself in the temple. 1 Kings 8:10 says, "the cloud filled the temple of the Lord." This imagery speaks of God's holy, divine presence. We have seen this imagery before. After leaving Egypt, God led his people through the desert. Exodus 13:21 says, "By day the Lord went ahead of them in a pillar of cloud to guide them on their way and by night in a pillar of fire to give them light, so that they could travel by day or night" (cf. Ex. 40:36-38). Then at Mount Sinai God revealed himself in a cloud (Ex. 19:9; 24:15-18). When the tabernacle was constructed, God covered it with the cloud of his glory (Ex. 40:34, 35; Lev. 16:2). This all speaks of God's presence! The use of such images of God in these ways was to instruct the people of that era - as it should be to us (Rom. 15:4). It should be understood that the visible revelation of God was sometimes in the context of a storm-like event (clouds, rain, thundering, darkness, etc.). Psalm 29, a praise song to God the King, is helpful on this point. The Psalmist writes:

Ascribe to the Lord, O mighty ones, ascribe to the Lord glory and strength. Ascribe to the Lord the glory due his name; worship the Lord in the splendor of his holiness. The voice of the Lord is over the waters; the God of glory thunders, the Lord thunders over the mighty waters. The voice of the Lord is powerful; the voice of the Lord is majestic. The voice of the Lord breaks the cedars; the Lord breaks in pieces the cedars of Lebanon. He makes Lebanon skip like a calf, Sirion like a young wild ox. The voice of the Lord strikes with flashes of lightning. The voice of the Lord shakes the desert; the Lord shakes the Desert of Kadesh. The voice of the Lord twists the oaks and strips the forests bare. 
And in his temple all cry, "Glory!" The Lord sits enthroned over the flood; the Lord is enthroned as King forever. The Lord gives strength to his people; the Lord blesses his people with peace.

Psalm 29 uses themes that were common for that day. Note how it uses words like waters (vs. 3), thunder (v. 3), lightening (v. 4-9), and flood (v. 10)). The use of this wording directs our attention to other religions of that era, especially the worship of Baal who was the storm god. In the notes of Spirit of the Reformation Study Bible, Dr. Richard Pratt writes, "The Canaanites believed that Baal provided rain and fertility, and that his power was seen in the storm. They called him 'cloud rider' in their religious texts. But the Lord controls nature (cf. 1 Kings 18)." The imagery in these verses was useful for God's people to better understand God's power as opposed to that of false gods.