I lost a ni cad glow battery last year and it was found and placed near where I fly and the next day I found it. Since then I marked the batteries with a magic marker but that ink wears off. So while charging some of the batteries I got the idea to use some of the address labels that come unsolicited in the mail.
  After cleaning the batteries with alcohol I applied a label to each battery and covered it with Scotch tape. That should keep them closer to home.
  Another use for the labels is to use them when signing in at a contest. A lot faster than writing the whole address.