Battery capacity bad

Have the battery pack can be unfortunately a quarter. The first charge (4 batteries) in my flash unit were empty after a short time.
Only after a further charge the flash with new batteries, I noticed, that can not be good, the charge of the cells.
I then measured the open-circuit voltage of the remaining unused batteries, no battery has come about 1.45 volts. Typical values ​​are about 1.55V at room temperature.

Not recommended my opinion :-)