lm358 alkaline battery charger circuit diagram

There are two different opinions on whether alkaline batteries can be charged. Some say it can be recharged and the effect is very good. Some say it should never be recharged, as the battery instructions warn of the risk of explosion. In fact, alkaline batteries are indeed rechargeable, and the number of recharges is generally about 30-50 times.

In fact, it is due to the mastery of charging methods that leads to two completely different consequences. First of all, there is no doubt that alkaline batteries can be recharged. At the same time, in the battery instructions, it is mentioned that alkaline batteries are not rechargeable and charging may cause explosion. This is correct, but note that the wording here is " may " cause an explosion. You can also understand it as a disclaimer of self-protection statement from the manufacturer. The key to charging alkaline batteries is temperature. As long as it can be done The charging process can be completed smoothly without high temperature when charging the battery. The correct charging method requires the following points:

1. Small current 50MA

2. Don’t charge 1.7V, don’t discharge 1.3V

After some people tried charging, they categorically said that they could not charge. The reason for problems such as no charging, short power use time, leakage, explosion, etc. was mostly due to the charger. If the charging current of the charger is too large, it will far exceed the charging current. 50ma. For example, the charging current of some fast chargers is above 200ma. The direct consequence is that the battery temperature is very high and it is hot to the touch. It may leak in some cases and explode in severe cases.

Some people use nickel-metal hydride rechargeable battery chargers to charge. Low-end chargers do not have an automatic charging stop function. Long-term charging may cause the battery to overcharge and cause leakage and explosion. Better chargers have an automatic charging stop function, but the charging stop voltage is generally set to 1.42V for nickel-metal hydride rechargeable batteries , while the full voltage of alkaline batteries is about 1.7V. Therefore, if the voltage is too low, it feels like it cannot be charged, and the power usage time is short, and it has no effect. Another thing is that not charging the battery means not waiting until the battery is completely dead before charging. If you do this, no matter how good the battery is, it can only be charged three or five times, and the effect is poor.

It is generally recommended to use Nanfu alkaline batteries with a voltage of not less than 1.3V. Therefore, if you plan to charge alkaline batteries, you must have a qualified charger with a charging current of about 50ma and a charging cut-off voltage of about 1.7V. Take a look at your home charger.

There are special chargers for alkaline batteries on the market, so-called patented products. In fact, it is a simple circuit with a charging voltage of 1.7V and a current of 50ma. Using the existing parts LM358 and TL431 on hand, I made a simple circuit that automatically stops charging when the cut-off voltage is 1.67V. The cost is only two yuan. For reference by interested friends.

Related instructions:

Alkaline manganese rechargeable battery : It is developed on the basis of alkaline zinc manganese battery. Due to the application of mercury-free zinc powder and new additives, it is also called mercury-free alkali manganese battery. This kind of battery can be charged and used dozens to hundreds of times without changing the discharge characteristics of the original alkaline battery, which is relatively economical and affordable.

Alkaline zinc-manganese battery, referred to as alkaline manganese battery, was successfully developed in 1882, developed in 1912, and was put into production in 1949. It was found that when KOH electrolyte solution is used instead of NH4Cl as the electrolyte, there are major changes in both the electrolyte and the structure, and the specific energy and discharge current of the battery can be significantly improved.

Its features:

1. Open circuit voltage is 1.5V;

2. The working temperature range is between -20℃~60℃, suitable for use in alpine areas;

3. The capacity of large-current continuous discharge is about 5 times that of acidic zinc-manganese batteries;

4. Its low temperature discharge performance is also very good.

The number of charging times is within 30 times, usually 10-20 times. It requires a special charger and it is extremely easy to lose the charging ability.