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Many people have bad habits, often leaving electric vehicle batteries on the car when they are not at home, not turning off the air switch, and not riding for several months. When I rode again a few months later, I found that the car was out of battery and couldn't charge properly. The charger is plugged in, but it remains green even after 24 hours because the battery voltage is too low. If there is a large difference between the output voltage of the charger and the battery voltage, the charger will not be able to charge the battery. This situation is commonly referred to as the battery starving to death.
This article will answer how to revive a lithium battery and tell the precautions and rescue measurements for users to protect their lithium batteries. For those wondering how to revive a lithium battery safely, understanding these principles is the first step.
What's a dead lithium battery
The phenomenon of lithium batteries starving to death usually refers to the situation where the voltage of the battery is too low due to excessive discharge, making it unable to charge properly or completely damaged. This phenomenon is mainly caused by chemical and physical changes inside the battery. Recognizing these changes is critical when planning how to revive a lithium battery effectively.
What causes a dead lithium battery
Excessive discharge leads to structural damage
Dissolution of negative copper current collector Excessive discharge can cause oxidation and dissolution of the copper foil on the negative electrode, damaging the electrode structure.
SEI film decomposition
The solid electrolyte interface (SEI film) that protects the electrode is damaged, which consumes lithium ions and reduces battery capacity when recharged. Electrolyte decomposition means under low voltage, the electrolyte may decompose and produce gas, causing expansion or leakage. These reactions complicate the process of how to revive a lithium battery and require specialized techniques. The normal voltage range of lithium batteries is 3.0V~4.2V (taking a single cell as an example).
When the voltage drops below 2.5V
The protection board triggers the "lock up" of lithium batteries, which are usually equipped with a protection board (BMS). When the voltage is too low, the output will be cut off to prevent further discharge. But if not charged for a long time, self discharge (about 1%~5%/month) will still cause the voltage to continue to drop, ultimately leading to the complete shutdown of the protection board and inability to wake up.
Chemical active substance deactivation
Under long-term low pressure conditions, positive and negative electrode materials (such as lithium cobalt oxide and graphite) may undergo irreversible lattice collapse, leading their lithium battery capacity loss. This irreversible damage underscores why learning how to revive a lithium battery early is crucial.
How to revive a lithium battery
Use a charger with a "repair mode" for low current activation, and attempt to charge with a small current of 0.05C~0.1C (100mA~200mA if the battery capacity is 2000mAh). Gradually increase the voltage to above 3.0V before charging normally.
For example, using a computer USB port: Connect the phone to the computer's USB port through a data cable (not a fast charging port, our traditional 5v-500ma or 5v-1A original charger), because the current output of the computer's USB port is relatively low, suitable for initial battery wake-up.
Be patient and wait. After connecting, do not rush to operate the phone. Let the phone charge for at least 2-3 hours without human intervention. During this period, there may be signs of the battery icon flashing or slowly increasing power on the phone screen, indicating that the battery is being activated.
Note that some protective boards may be permanently locked and require professional equipment to reset. Handle with caution Batteries that are swollen, leaking, or overheating should be immediately stopped as there is a risk of combustion. Non professionals are not recommended to disassemble batteries, as the electrolyte is corrosive and toxic.
Scenes may cause dead lithium battery
Not only do mobile phones experience the phenomenon of "starvation", but also devices and tools with batteries that we use in our daily lives may experience this situation. Please pay attention to prevention.
Backup electronic devices
Backup phones, tablets, drones, etc.
Seasonal products
Electric bikes (parked in winter), camping lights, electric bicycles.
Low power devices
Electronic scale, remote control, temperature and humidity meter (using button lithium batteries).
These electrical devices may all experience excessive discharge, leading to their inability to function properly. In such scenarios, knowing how to revive a lithium battery can save both money and resources.
How to recharge a dead lithium ion battery
When the battery is starved, most of the time it is replaced. But replacing a set of batteries can cost hundreds, so it's a bit regrettable, especially for batteries that have just passed warranty.
Here are several methods to activate the sleep state of lithium batteries:
Principle of slow charging activation method
Using low current charging can allow sufficient time for the chemical substances inside the battery to reactivate and react uniformly, avoiding the damage that high current charging may cause to the battery.
Connect the lithium battery to a charger that matches its rated voltage, and set the charger's current to a lower level (usually 0.1C-0.2C, where C is the unit of battery capacity, such as 1000mAh, 0.1C is 100mA). Continuously charge for a period of time, which may take several hours or even longer, during which observe whether the battery voltage rises. When the voltage rises to a certain level (usually above 3V), the battery may be activated. This slow-charge method is a foundational strategy for how to revive a lithium battery without risking further damage.
Principle of pulse charging activation method
By sending a series of pulse currents to the battery, these pulses can help break the passivation layer that may form on the battery plates, allowing ions inside the battery to move freely again and activate the battery.
This method usually requires a professional pulse charger. Connect the lithium battery to a pulse charger and set appropriate pulse parameters according to the charger's instructions, such as pulse width, pulse interval, and pulse amplitude. Then turn on the charger for charging, and pay attention to monitoring the changes in battery voltage and temperature during the process. Pulse charging exemplifies how to revive a lithium battery using advanced electrochemical interventions.
Principle of parallel activation method
Connect a lithium battery of the same specifications and sufficient power in parallel with a dormant lithium battery, allowing the healthy battery to deliver a certain amount of power to the dormant battery, increase lithium-ion battery voltage, and activate the dormant battery.
Ensure that the specifications (such as voltage, capacity, etc.) of the two batteries are exactly the same. Connect the positive and negative terminals of two batteries. After connecting, keep them connected for a period of time, usually a few hours later, and check if the voltage of the dormant battery has returned to normal. However, this method requires attention to the firmness of the connection and the positive and negative poles of the battery to avoid short circuits. While risky, this method demonstrates creative approaches to how to revive a lithium battery in emergency situations.
The precautions to avoid dead lithium battery
When not in use for a short period of time
- Keep the battery level between 20% and 80%.
Avoid storing with full or empty power, the ideal storage voltage is 3.6V~3.8V (about 50% of the battery capacity).
- Turn off the device power
Some devices, such as bluetooth earphones and power tools, slowly consume power even when turned off and require a complete power outage.
Long term storage (over 1 month)
- Regularly replenish electricity
- Check the battery level every 1-2 months, and if it is below 40%, charge it to 50%~60%.
- Control the ambient temperature
Stored in a dry environment between 15 ℃ and 25 ℃, high temperatures can accelerate self discharge, while low temperatures may cause lithium deposition.
Optimization of usage habits
Avoid completely depleting the battery.
Charge the device promptly when it prompts low battery (such as 20%).
Use original charger, poor quality chargers may cause uneven charging or abnormal voltage.
To deactivate old equipment, the battery needs to be removed.
If the camera or remote control is not used for a long time, remove the battery and store it separately.
Conclusion
The essence of "starvation" in lithium batteries is chemical damage caused by excessive discharge. Mild low voltage states can be activated by small currents (such as 0.1C slow charging or USB interface wake-up), but batteries that have triggered electrolyte decomposition or copper foil dissolution pose a risk of permanent failure.
Repair must strictly follow safety guidelines
Immediately stop using batteries that have expanded or heated up, and avoid non professional disassembly.
Long term protection is better than post remedy. Daily storage should maintain 50% battery capacity and be regularly recharged.
Use original chargers to balance voltage. Combined with the earlier methods on how to revive a lithium battery, these precautions form a comprehensive battery management system.
If the battery capacity decays by more than 30% or multiple activations are ineffective, it is recommended to replace the battery with a new one to ensure safety and endurance performance.
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