很多便携式监护仪为交直流两用 ,内置电池 ,这给移动和野外使用及需要连续工作的场合带来了方便。但此类机器充电电路不很完善 ,一般没有电池温度检测及电池放电回路 ,再加上电池多为Ｎｉ -Ｃｄ和铅蓄电池 ,容易老化和过充电 ,在使用几年后机器容易发生故障。这类机器的电池在 Many portable monitors are AC/DC, built-in batteries, which bring convenience to mobile and field use and need to work continuously. However, this kind of machine charging circuit is not perfect, generally there is no battery temperature detection and battery discharge circuit, plus the battery is mostly Ni-Cd and lead batteries, easy to aging and overcharge, after a few years of use the machine is prone to failure. The battery of this type of machine is