I think I know of the book you are talking about, I saw it when I went in to buy Willful Murder: The Sinking of the Lusitania. I always flick through shipping books and the likes, and was particularly touched by this one. Although it will never have the everlasting interest of Titanic or the contraversy of the Lusitania (atleast not as much as), it will always be something we remember.
I saw something on the History Channel a few months ago on this and one of the conclusions offered was that it was one, possibly two of the Kursk's torpedos that exploded. Apparently, the things are fueled by hydrogen peroxide, (Lovely stuff!) and the things had a tendency to leak!
I think the Russians themselves have now officially accepted this as the cause too... after all the earlier accusations about American/British/just-about-any-other-western submarines colliding with her!
Apparently some time in the 1950's (I think) a British Submarine using experimental torpedoes also fuelled by hydrogen peroxide was lost in very similar circumstances. As you say - it's hellishly unstable stuff.
From the Kursk right back to the Hunley who knows how many men have died horribly in submarines. As Alex says - this is a good day to remember them.
As I recall, the Germans tried using hydrogen peroxide for submarine propulsion during World War II. Not hard to see why as making a success of the system would mean that submarines wouldn't have to surface where they would be vulnerable to attack. One little problem though, these Walther boats had an unfortunate tendency to explode, so they never got past the experimental stage.
Unfortunately, when a few examples were taken intact at war's end, the Royal Navy thought they were looking at a mature design, so they had a go at it too, and with the same results. The boat equipped with this system wasn't called "The Exploder" for nothing.