back up battery

基本解释

Widely used in battery back up power systems and solar systems.
广泛使用的电池备份的电力系统和太阳能系统。
However, from now on he hasn't been forget in the pocket to put one section back up battery.
不过，从此以后他一直没有忘记在口袋里放一节备用电池。
The PV cells are mounted on a pergola in the garden. A back-up battery ensures the operation of essential services in the event of power failure.
备用电池可以保证在PV系统无法供电又停电的情况下基本系统的运行。

The SMILE Plug includes a 5V Lithium-Ion polymer battery for back-up power, making it ideal for learning environments where electrical power can be inconsistent.
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After charging up the battery, sliding it into the rack system at the back of the bike (which could not be simpler), and locking it into place, you're ready to go.
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Xperia ZL also includes Battery STAMINA Mode that significantly improves the battery standby time by automatically shutting down battery-draining apps whenever the screen is off and starting them up again when the screen is back on.
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