The batteries have to store a lot of energy in a small, light package, scoring high in a quality known as energy density.

新型电池必须在轻小的电池组里储存大量电能，在能量密度上表现出高评分。

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Electrolyte was one of the key points which made rechargeable lithium ion batteries with high power and energy density, long cycling life and desirable safety.

电解质是制备高功率密度和高能量密度、长循环寿命和安全性能良好的锂离子电池的关键材料之一。

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Lithium ion batteries are attracting more attentions for their superior properties like high voltage, high energy density, high-speed discharge, low self-discharge, low toxicity, etc.

锂离子电池具有比能量高、体积小、质量轻、可高速率放电、自放电率低、循环寿命长、无毒等优异性能而倍受世人青睐。

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We're resigned to the fact that the constantly increasing power demands of modern gadgets will always outstrip slow increases in the energy density of batteries: however, high energy density is not the only factor that goes into making a good battery.

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This type of battery has an unusually high energy density, which means the units can be smaller and thus lighter for a given amount of power than traditional batteries.

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