One side had electrical contacts for all 26 letters.
它一面有 26 个接触点，代表 26 个字母。
Electrical contacts
原声例句
计算机科学 Crash Course
经济学人-科技
Researchers at Graz University of Technology in Austria, for example, have developed a version that has its electrical contacts coated with carbon which is pierced by tiny pores.
例如，奥地利格拉茨科技大学的研究人员已经开发出了一种电触点上涂着能被小孔穿透的碳的电池。
双语版 TED-Ed 演讲精选
It also results in a bunch of side reactions that produce useless contaminants, reducing a battery's capacity, and it could even damage the internal structure of the battery, leading to a loss of electrical contact and failure.
还会引发一连串的副反应，产生无用的污染物，损害电池的容量，甚至可能损坏电池的内部结构，形成断路导致电池失效。
TED-Ed（视频版）
It also results in a bunch of side reactions that produce useless contaminants, reducing a battery's capacity; and it could even damage the internal structure of the battery, leading to a loss of electrical contact and failure.
它还会导致一系列副反应， 产生无用的污染物，从而降低电池的容量；甚至可能损坏电池的内部结构，导致电气接触丧失和故障。
英语百科
Electrical contacts
An electrical contact is an electrical circuit component found in electrical switches, relays and circuit breakers. Each contact is a piece of electrically conductive metal. When a pair of contacts touch, they can pass an electrical current; when the pair is separated by an insulating gap, then the pair does not pass a current. When the contacts touch, the switch is "closed"; when the contacts are separated, the switch is "open". The gap must be an insulating medium such as air, vacuum, oil, SF6 or other electrically insulating fluid. Contacts may be operated by humans in pushbuttons and switches, by mechanical pressure in sensors or machine cams, and electromechanically in relays. Contact materials are usually composed of superior conduction materials such as silver or gold. Cheaper metals may be used to reduce costs for the main contact bump and plated with superior metals.