them LED lamps/torches - what batteries do they use?

I got 2 of them Luxeon XML LED lamps and rewired my battery so that I can run both from same battery.

Joy and much light in the dark but the battery gave out after maybe 15 to 20 min (ok, so was it not fully charged but still is not quite long enough for my home journey).

The battery pack has 4 cells wired in parallel comprising these blue cells, about the diameter of AA but maybe 1/2 times as long, fully charged 3.9 to 4.0ish volts.

What type are these?

And the actual question, is this type of battery pack available in larger capacity?

Most use 18650 Li-ion: http://www.ebay.co.uk/sch/Multipurpose-Batteries-Power-/48446/i.html?_ipg=25&_from=&_nkw=&_armrs=1&_ssn=big_f_d_d

The more mAh, the higher the capacity of the battery.

yep them is the one.

4600 and 4800 mAh are available at reasonable price .....

will search a bit more (need to find out what I have fitted)

Worth a read: http://www.torchythebatteryboy.com/p/18650-batteries-chargers.html

^^^ good find and makes for some interesting reading.

the data seem to focus on solely on battery life and not how flat the voltage is.

found out from seller thay my pack is 5200 mAh so 1300 per cell; seems I can triple or nearly quadruple the capacity.

A fullly charged pack will see me home plus some - not sure how much more since I do plan to do a few night rights wehn it gets a bit warmer and drier, no chance of that any time soon.

I think they are wired as 2 lots of 2 cells in seires to make 8ish volts in parallel, if that makes sense. So you could wire one light to each pair.

it's ok, I know how they are wired.

trawling the web, one thing I found is that the highest caapcity is around 2800; there are many unknown brand batteries from Taiwan/China that claim to be as high as 4800 mAh but it is a pack of lies.