With a large, bright screen and inability to remove the battery in the iPhone 4, getting a secondary power source is inevitable if you can't guarantee a power point on your travels.

旅行时没法充电，iPhone 4屏幕硕大闪亮，再加上内置电池无法取出，是时候准备一个备用电源了。

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Such displays differ from each other in the charging mode and the discharging mode of the secondary battery.

这样的显示与二级电池在充电模式和放电模式中的显示都彼此不同。

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Nowadays, the novel secondary lithium battery is widely used for it is safe and reliable, small and light, good for environment protection with high power density.

当前，安全可靠、有利于环保、高功率密度、体积小、重量轻的新型二次锂电池正被广泛应用。

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The immediate goal is to develop a secondary battery for an EV that could provide extra mileage in a matter of seconds.

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Let's focus on the actual machine first: here we have a Core i5-2410M (2.3GHz to 2.9GHz) rig packing a 14-inch 1, 366 x 768 LCD, Intel HD Graphics 3000, 4GB of DDR3 RAM, 500GB 7200rpm hard drive, and a DVD burner that can be swapped with a secondary battery.

ENGADGET: Gigabyte M2432 laptop with GeForce GT 440 graphics card dock hands-on

Without being prescriptive it is expected that a typical station configuration will consist of a primary tide gauge, two under water pressure sensor (secondary tide gauge), data logger, DCP geostationary satellite transmitter, modem, battery backup, solar panel, cables, mountings.

UNESCO: EDUCATION