Lithium-ion

As if keeping modern mobile phones charged wasn’t hard enough already, it’s about to get a whole lot more annoying.

For ‘security’, passengers flying to the US will now be required to demonstrate that their electrical devices turn on, and gadgets with flat batteries won’t be allowed on the plane. This is, apparently, so that al-Qaeda can’t replace the batteries with something even more explosive than lithium-ion cells.

However, I see a problem:

1. Modern electronic devices use lithium-ion cells.
2. Lithium-ion cells have a standard voltage, which is determined by their chemistry.
3. Higher voltages (multiples of the cell voltage) are obtained by connecting multiple cells in series.
4. The difference between a large lithium ion cell and a small one is that the bigger one lasts longer. (You also have to worry about the maximum discharge rate, but my back-of-the-envelope calculations suggest that’s not a problem.)

In other words, it seems quite possible to strip out most of a laptop battery, replace it with a solid block of C4, and fit enough small cells in the space that’s left to power it on long enough to get through security.

Now, I don’t know where to get a block of C4, and I’m certainly not interested in blowing up any aircraft, least of all one I’m flying on! However, I do know where to buy small lithium-ion cells, and if I can order them from China via eBay, terrorists can probably manage it too.

Nine to five

I remember a couple of songs from my childhood—Dolly Parton’s Nine To Five and Michael Jackson’s The Way You Make Me Feel—that featured the idea of working from 9am to 5pm in their lyrics.

Entering the professional world of work was, therefore, something of a let-down for me: the nominal hours were always longer, and no one ever left on time. More…

Pick and place

This is the story of the worst job I ever had. More…

The price of a stamp

Last week, I sent a postcard from Japan to the UK. It cost me ¥70, about 41p at current rates. Today, I sent a postcard from the UK to Japan. That cost me 97p, over twice as much. More…

A song that reminds you of someone

Best bit about working with Paul was how cynical and dour he was. A bird of my feather.

More…

Older entries can be found in the diary section.