We had a similar issue once with the Minimed pump and I think ours had to do with a problem with the battery cap. Medtronic sent a new one and the problem was corrected. Medtronic suggests Energizer for the Minimed pump. Our insurance company pays for the batteries. The medical supply company that sends our supplies to us also send batteries every 3 months. Not sure if that is an option for you but maybe you can call the insurance company and ask. In order to get our supplies from the medical supply company vs. Medtronic we had to sign up for a Diabetes Management program that our insurance company offers.
From the Animas site:
Q: How often should I change my Battery Cap?
A: Your battery cap should be changed every six months. If you are a frequent swimmer or work in a dusty environment it is recommended to change your cap every three months.
Q: What is the warranty of a battery cap?
A: Your Animas® insulin pump maintenance part (battery cap, cartridge cap) is warranted against defects in materials and workmanship for a period of six (6) months from the date of original retail purchase.
Q : What type of battery can my pump use (OneTouch® Ping® Animas®2020, Animas®1250 and Animas® 1200 insulin pumps, )?
A: Your pump is designed to achieve optimum performance and battery longevity with an Energizer Lithium L91 AA battery (1.5v)
Q: Can I use an Alkaline AA battery in my pump?
A: Yes, it is possible to safely power your pump with a conventional alkaline battery 1.5V, but the battery life is significantly reduced. Be sure you select the correct Battery Type on the VERIFY screen when you change the battery to ensure accuracy of battery life indicator