I asked the local store what I should pay for a battery pack for a Compaq LTE 5100 laptop. The price was DKK 1,750.00 (~ USD 220.00) which I think is too much. I then bought ten NiMh cells from the local store for the price DKK 585.00 (~ USD 74.00) and solded them in the original pack.
Not very nice but it works:
And you will not like to see the top cover after I have removed it :-)