The last 2 times Max's pump batteries have died they have gone from 3 bars to dead overnight! I just started using the Energizer lithium batteries because with CGMS the normal batteries seemed not to last too long. Last night at bedtime, Max's battery looked fine. This am he checked himself and was 212 (high for him in the am). When I told him to correct, he said his pump was dead. We changed the battery and it had gone dead at 5am. According to his CGMS the last reading was 108 at 5am and by the time we checked at 7am he'd gone up 100 points without any insulin. It's so dangerous- I can't imagine what he'd have been if it had died shortly after I'd gone to bed. Wanted to pass it along to people who didn't know and get advice from others about what batteries they use? Are any of you using Lithium? Should I just get in the habit of changing the battery weekly/every 2 with the CGMS sensor?