The battery on my NEC Versa 6050MH dropped rather suddenly from 83% charges to 8% charged while I was coppying files to a floppy. Now the charge does not build up on it. Is there some way to check that the problem is the battery before shelling out almost $200 for a new one?

Measure the voltage with a voltmeter. A nickel hadride battry pack is made by connecting 8 cells in series to get 9.6 volts or 10 cells for 12 volts. Each cell is 1.2 volt. When charging the cell voltage goes up to 1.4 volts. A common problem with Nicad cells is is they develop internal shorts and suddenly the cell won't charge anymore. The short is caused by wiskers of cristaline nickel growing inside the cell. I found this happens when the battery is more than a year old. When one of the cells loses capacity faster than the rest that cell will drop to zero volts first and be "charged backwards" if you continue to use the battery pack . When a pack is new you should let it run down and imediatly recharge to prevent the cells from losing capacty. Older cells also benifit from "cycling" but be nore careful to not let them run down completly. People who sell Nicads store them in a refrigerator to slow down the aging proccess during storage. To test a discharged battery first charge it for 15 minuits and measure the voltage. It will be a multiple of 1.2 volts x the number of good cells. A shorted cell can be "zaped" to remove the nickel wiskers. The longer the cell is in the shorted condition the less likely this fix will be permenent. Charge a electrolitic capacitor to 30 volts and discharge it across the battery terminals. Charge again for 15 min and recheck. Then cycle the battery a few times to even out the capacty of the cells.

tell me , if i have a pack of nickel metal hydryde it is able to the procedure of the capac itor? and whats the best value of capacitance to get the best? my throuble was than just for a few days the batery works well but i didnT use the computer for a long time and since that the battery never work.