Canon PowerShot S1 IS PowerShot S1 IS Camera User Guide - Page 143

- When charging the batteries (insert and remove the batteries two or three times before charging) - When charging completes in a matter of a few minutes (the battery charger indicator remains lit) zYou may not be able to fully charge the batteries due to their specifications right after purchase or after long periods of non-use. If this happens, use the batteries until their charge is depleted before charging them again. After doing this several times, battery performance will be restored. zSince storing fully charged batteries for long periods of time (about 1 year) can shorten their lifecycle or affect performance, you are recommended to use the batteries in the camera until they are completely discharged and to store them at normal temperature (23 °C/73 °F) or less. If you do not use the batteries for long periods of time, charge them fully and discharge them fully in the camera at least once a year before returning them to storage. zIf battery usage time is considerably low despite their terminals being wiped and the battery charger's indicator remaining lit, it is possible that the batteries have reached the end of their lifespan. Switch to different, unused batteries. If you are purchasing new batteries, look for Canon's AA-size NiMH batteries NB4-200 (a NB-2AH four-battery set). zLeaving batteries in the camera or charger may damage it causing battery leakage. Remove batteries from the camera or charger and store in a dry cool location when not in use. Appendix 141