Okamoto Eiji, Watanabe Kazuya, Hashiba Kunihiro, Inoue Taku, Iwazawa Eichi, Momoi Masato, Hashimoto Takuya, Mitamura Yoshinori
Department of Information Science, School of Engineering, Hokkaido University, Sapporo, Japan.
ASAIO J. 2002 Sep-Oct;48(5):495-502. doi: 10.1097/00002480-200209000-00010.
An implantable secondary battery is one of the key components in a total artificial heart system. Because a 2 year cycle life is required, the cycle life of the secondary battery as well as its charge and discharge properties are important parameters for selection of an appropriate battery. We carried out cycle life tests on four kinds of rechargeable batteries (a Ni-MH secondary battery, a Ni-Cd secondary battery, a Li-ion battery with a graphite anode, and a Li-ion battery with a nongraphitizable carbon electrode) to determine their suitability as implanted back-up batteries. Each of the batteries was charge/discharge cycled at 37 degrees C to 39 degrees C using a charge current of 1 C ampere, and they were each fully discharged under either pulsatile discharge loads, which mimicked pulsatile operation, or a nonpulsatile load equivalent to the average of the pulsatile loads. The two Li-ion batteries made by different manufacturers both met the minimum requirement of cycle life of more than 1,500 cycles, considering safety coefficient regardless of the discharge pattern. In addition, the temperature increase of these Li-ion batteries (3 degrees C) was lower than that of Ni-Cd and Ni-MH batteries (15-25 degrees C). Out of these four batteries, the two Li-ion batteries are the most suitable for use in a totally implantable artificial heart system.
植入式二次电池是全人工心脏系统的关键部件之一。由于需要2年的循环寿命，二次电池的循环寿命及其充放电性能是选择合适电池的重要参数。我们对四种可充电电池（镍氢二次电池、镍镉二次电池、带石墨阳极的锂离子电池和带不可石墨化碳电极的锂离子电池）进行了循环寿命测试，以确定它们作为植入式备用电池的适用性。每种电池在37摄氏度至39摄氏度下以1C安培的充电电流进行充放电循环，并分别在模拟脉动运行的脉动放电负载或相当于脉动负载平均值的非脉动负载下完全放电。无论放电模式如何，考虑到安全系数，不同制造商生产的两种锂离子电池均满足循环寿命超过1500次的最低要求。此外，这些锂离子电池的温度升高（3摄氏度）低于镍镉和镍氢电池（15至25摄氏度）。在这四种电池中，两种锂离子电池最适合用于完全植入式人工心脏系统。
