镍氢电池失水原因

镍氧电池内阻增大的原因是在每次充电的末期，内部连带发生电解水的化学反应使内部压力增高，虽然大部分气体可以重

新化合成水，但是在高压的情况下，还是会有一部分气体通过安全阀溢出。久而久之，内部就严重缺水了。

现在的镍氢电池容量都做得很大，内部结构紧凑，所以储水量就已经很小，再加上现在都是用快速充电器充电，使得末期内部压力更高，镍氢电池便严重折寿!有的甚至循环不了100次就挂了。

可以见得:严重失水的电池只要通过某种方式加入一定量的水便可以恢复性能。但是一般的办法在加水的同时会破坏安全

阀，使得加水后的由池只可用几次就再次报废，必须找一个好办法在不破坏安全阀的同时加水。

严重失水的镍氧电池特点:容量减少不严重，但是快速充电器不再支持充电，用慢充充满电后端电压很高，放电电流确很

小，甚至短路电流只有几百mA，慢慢放电却可以放出很大的有效容量。

镍氢电池修复方法

第一步:把电池脱光光后彻底放电，根据电池情况可以直接短路或者用1欧电阻当负载放电到端电压接近0V，一般需要5-10小时。这样可以防止加水后不小心引起电池短路烧坏电池，又可以减轻浸水时的电化学腐蚀。

第二步:打开安全阀。像SONY等品牌的电池正极外有四个孔，可以直接看到安全阀的橡胶帽，用一节细铁丝弯成

U型，然后从橡胶帽底端向中心位置插入大约2mm。这样安全阀就被迫开启了，弯成U型是为了不损伤橡胶帽。

第三步:用刚烧开的开水烫电池，等到正极不再冒泡泡为止，但是不可以煮电池!!立刻扔到凉(室温即可)纯净水里瓶

里，等待1分钟左右，此时部分水已经吸入，随即拧死瓶盖用力挤压瓶子大约10秒，已让更多的水进入电池。

第四步:拿出电池，擦干，拔出U型铁丝，套皮。最好用大十字螺丝刀配合小锤，把正极帽中心位置略砸凹，以增大安全

阀密封度，凹下去0.5mm即可，砸多了危险。

第五步:放置5小时以后开始进行反复3-5次的充放电。第一次充电先用快充充大约半小时，然后用慢充充电到端电压

1.45V以上(很长时间)，之后用中速或者慢速充电器即可。

最后一步:重新定容。先充满电后放置5小时，然后采用“ZB210多功能电池容量测试仪”以1A横流放电到终止，然后把容

量(精确到10mAh，四舍五入)用油漆笔标在电池上。

OK!大功告成!这些电池加水后容量还是很高的啊，充满电用数码相机测试，闪光灯回电时间只有2秒，和新买的碱性电

池速度差不多，这个容量能昭多少照片就不用说了。

Causes of water loss in NiMH batteries

The reason for the increase in the internal resistance of the nickel-oxygen battery is that at the end of each charge, the internal chemical reaction of electrolyzed water increases the internal pressure, although most of the gas can be regenerated.

Newly synthesized water, but under high pressure, a part of the gas will still overflow through the safety valve. Over time, there is a serious shortage of water inside.

Nowadays, NiMH batteries have a large capacity and compact internal structure, so the water storage capacity is already very small. In addition, they are all charged with fast chargers, which makes the internal pressure higher in the final stage, and the life of NiMH batteries is seriously shortened! Some even hang up after 100 cycles.

It can be seen that a battery with severe water loss can restore its performance as long as a certain amount of water is added in a certain way. But the general method will destroy the safety while adding water

valve, so that the pool after adding water can only be used a few times before being scrapped again. We must find a good way to add water without destroying the safety valve.

The characteristics of nickel-oxygen batteries with severe water loss: the capacity reduction is not serious, but the fast charger no longer supports charging, and the back-end voltage is very high when fully charged with slow charging, and the discharge current is indeed very high.

Small, even the short-circuit current is only a few hundred mA, but slowly discharging can release a large effective capacity.

Ni-MH battery repair method

The first step: completely discharge the battery after stripping it. According to the battery condition, it can be directly short-circuited or discharged with a 1-ohm resistor when the load is discharged to a terminal voltage close to 0V, which generally takes 5-10 hours. This can prevent the battery from being accidentally short-circuited and burnt out after adding water, and can also reduce electrochemical corrosion when immersed in water.

Step 2: Open the safety valve. There are four holes outside the positive pole of batteries from brands such as SONY, and you can directly see the rubber cap of the safety valve, which is bent with a thin wire.

U shape, and then insert about 2mm from the bottom end of the rubber cap to the center. In this way, the safety valve is forced to open, and it is bent into a U shape so as not to damage the rubber cap.

Step 3: Use just boiled water to scald the battery, wait until the positive pole no longer bubbles, but do not cook the battery!! Immediately throw it into a bottle of cold (room temperature) pure water

Wait for about 1 minute, at this time some of the water has been inhaled, then screw the cap tightly and squeeze the bottle for about 10 seconds, so that more water has entered the battery.

Step 4: Take out the battery, dry it, pull out the U-shaped iron wire, and cover it. It is best to use a large Phillips screwdriver and a small hammer to slightly dent the center of the positive cap to increase safety

The sealing degree of the valve can be concave by 0.5mm, it is more dangerous to smash it.

Step 5: After placing for 5 hours, start to charge and discharge repeatedly 3-5 times. For the first charge, use the fast charge for about half an hour, and then use the slow charge to charge to the terminal voltage

1.45V or more (for a long time), then use a medium-speed or slow-speed charger.

The final step: re-volume. First fully charged and then placed for 5 hours, then use "ZB210 multifunctional battery capacity tester" to discharge with 1A cross current until termination, and then put the capacity

The amount (to the nearest 10mAh, rounded up) is marked on the battery with a paint pen.

OK! You're done! The capacity of these batteries is still very high after adding water. Tested with a digital camera when fully charged, the flash recycle time is only 2 seconds, and the newly purchased alkaline batteries

The pool speed is about the same, so it goes without saying how many photos this capacity can show.