From www.arissat1.org 11 Aug 2001
The Russian Silver-Zinc (Ag-Zn) battery that is powering ARISSat-1/RadioSkaf-B is the same battery that is used to power the Russian Orlan space suits. The battery is designed for a lifetime of 5 deep charge-discharge cycles when used in the spacesuit.
Using it in a spacecraft going through 14 shallow charge-discharge cycles per day is new territory.
12 days since activation time 14 shallow charge-discharge cycles per day =168 shallow charge-discharge cycles "Is shallow = normal charge- discharge?"
Some specs:
Silver-zinc batteries are available off-the-shelf and have a higher specific energy (130 Wh/kg) and density (240 Wh/litre) than most other commonly available secondary batteries. High cost, limited cycle and shelf life, and a long recharging process reduce its overall attraction. While at normal discharge rates, 40 to 50 cycles can be expected from the battery, this reduces to 10 or 15 at high discharge rates. Cycle life is also reduced if the battery is discharged below 80% of rated capacity and thus, a 20% reserve is required at the end of the mission. Silver-zinc batteries have been used extensively in AUVs and their performance is reliable and documented. Their high cost and short life have, however, prompted consideration of alternative technologies.
P.S. At 13 Aug 2011 04:44:03 UTC ARRISat-1 High Power mode has been reported over Australia
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