backup battery

基本解释

The brain requires a constant supply of energy and 'has only a limited backup battery, ' he says.
霍洛韦说，大脑需要持续供应能量，而且“只有有限的后备电池”。
(Power outages, however, activate backup battery and safe mode, which means you can still perform tasks like unlocking a door manually).
（比如停电了。但是还有启动备用电池和安全模式的存在，这样你就可以继续你手上的活计了）。
Technical challenges remain, including integrating a leakproof backup battery into the device and miniaturising the FREE-D’s control electronics.
存在的技术难题还很多，包括将一个防漏电的备用电池集成到心泵内，还有缩小FREE-D电子元件的体积。

After some fumbling in the dark I ripped out the failing 9-volt backup battery and it went dead.
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The homes will all have solar and backup battery systems.
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