What should I do if an electric vehicle's lithium battery cannot be charged without being used for a long time?

Have you ever encountered this situation when using an electric vehicle in daily life? The electric vehicle runs out of battery and when charging, it can't be charged for any reason. After the charger is plugged in, no matter how long you charge it, it always shows a green light. This is due to carelessness in daily life. When people are not around, they still put the electric vehicle battery on the car and the air switch is not turned off, and they don't ride for a long time, which ultimately leads to low battery voltage and inability to charge. What should we do in this situation?

The voltage of this type of battery pack is generally only around 5.6V and will not exceed 6V. For such batteries, most of them are replaced. But it's a pity to just replace a set of batteries that cost hundreds, especially those that have just passed warranty.

Here are five good methods that can save most of these batteries. Note that not all can be solved using this method.
1、 Special charger method.
Some chargers automatically recognize the battery voltage, and regardless of the voltage of a set of batteries, they can automatically recognize the voltage and charge it. For example, the original car had a 60V-20AH battery, but now it is less than 30V, so it can still be charged inside. As the voltage increases, it fully adapts to the higher-order voltage before charging the battery.

2、 Parallel connection method.
This method is a bit more complicated. For example, if the vehicle originally had a 48V-20AH battery, we will connect another set of 48V-20AH batteries in parallel. Everyone knows that the voltage in parallel circuits is equal everywhere, and the high voltage terminal will flow into the low voltage terminal. This method is also used by many battery dealers to detect completely dead batteries. Then charging can also achieve the purpose of charging. This principle is similar to connecting a battery in series. Also, increase the voltage of the entire group.

3、 Single battery charging method.
Charging a single battery with a 12 volt motorcycle charger can activate the battery, but this charging process is relatively slow, usually taking more than 7 hours for the battery voltage to slowly rise to around 12V. If all single blocks are charged, it will take a lot of time.

4、 Low voltage charging method.
Choose a smaller charger for charging. For example, if it is a set of 60V-20AH batteries, we use a 48V-20AH charger for charging. In most cases, it can also be recharged. The principle is also similar to the first one, which brings the charging voltage closer to the voltage at both ends of the battery.

5、 Series connection method.
Connect an additional 12 volt battery with normal voltage in series across the entire set of batteries. For example, if the original car had a 48V-20AH battery, we can connect an additional 12V-20AH battery in series. A fully charged 12V battery has a voltage of about 13V. After being connected in series, it can increase the voltage of the entire set of batteries, and then use its original charger for charging. This way, the battery can be charged in. After inserting the charger, the charger will turn red, and the battery can be charged in at this time. When the charger turns green, remove the battery that was connected in series. Then you can charge it normally.

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