Late last week, Apple announced to its dealers that it will be offering a free protective battery case to all existing PowerBook 140 and 170 customers, as well as including one of these cases with each PowerBook 140/170 and 140/170 battery sold in the future. Apparently the non-conductive case is designed to prevent the battery from short-circuiting.
The notice sent to dealers warned that batteries stored outside the PowerBook without any protective wrapping could short-circuit if metal came into contact with both battery terminals. This could result in burn injuries or fires. In the future, PowerBook 140/170 batteries will bear a warning label explaining the danger and stating that the batteries must be stored in the protective case when not installed in a PowerBook.
Apple is mailing letters to all registered PowerBook 140/170 owners this week, explaining the situation and providing instructions on how the owners can obtain the free protective case. PowerBook owners may visit their Apple dealer to get the case or call Apple at 800/377-4127. Note that since dealers have just been informed of this, most won't have the cases on hand right away. If your dealer is not aware of the situation, please refer them to part number 076-0590.
PowerBook 100 owners apparently don't need to worry about this issue. The design of the PowerBook 100's battery, which is different from the battery for the 140 and 170, may not be as susceptible to short-circuiting. The contacts on the 100 battery are recessed and not right next to each other; the 140/170 battery's contacts are only a millimeter apart and thus may be more easily short circuited by a paper clip or some such object. However, PowerBook 100 owners still need to be cautious, and should avoid setting a battery down on a conductive surface or object.