In the daily use of electric bicycles, electric scooters, drones, AGVs, and energy storage devices, overcharging and deep discharging are two major reasons for shortened lithium battery life and increased safety risks. Many battery problems do not stem from the product itself, but from incorrect usage and management.
This article, based on years of experience in battery research and development, BMS design, and practical applications, systematically analyzes the dangers of overcharging and deep discharging and shares practical prevention techniques to help businesses and users extend battery life and improve safety.
Part 1. What are Overcharging and Deep Discharging?
1. Overcharging
This refers to continued charging of the battery after it has reached its designed maximum voltage, which may lead to:
Cell overheating
Uncontrolled internal chemical reactions
Battery swelling or even thermal runaway
2. Deep Discharging
This refers to the battery voltage being discharged below the safe lower limit, which may cause:
Irreversible damage to the cell structure
Rapid capacity degradation
Inability to charge normally again
Note: Both of these situations will significantly shorten battery cycle life and increase safety hazards.
Part 2. Main Dangers of Overcharging and Deep Discharging
Significantly reduced battery cycle life
Poor cell consistency and unstable performance
BMS frequently entering protection mode
In severe cases, causing fire or equipment damage
For B2B customers, this is not only a product problem but may also lead to after-sales costs and brand risks.
Part 3.6 Key Tips to Avoid Overcharging
1. Use a matching charger
Ensure that the charger voltage and current parameters match the battery design, and avoid using non-original or mismatched charging equipment.
2. Avoid prolonged “overnight charging
The battery should be disconnected from the power supply promptly after being fully charged to avoid prolonged exposure to high voltage.
3. Choose batteries with intelligent BMS
An intelligent BMS can automatically cut off charging when the battery is fully charged, preventing the risk of overcharging.
4. Control the charging environment temperature
It is recommended to charge in an environment of 10°C–35°C, avoiding charging under high-temperature conditions.
5. Do not charge the battery in an abnormal state
If you find the battery swelling, overheating, or emitting an unusual odor, stop charging immediately. 6. Regularly inspect charging equipment
Aging or substandard chargers may cause abnormal output, leading to overcharging.
Part 4. 6 Practical Tips to Avoid Deep Discharge
1. Do not let the battery completely drain
When the device shows a significant decrease in power or a low battery warning, charge it promptly.
2. Avoid long-term storage with low battery
Leaving the battery in a low-power state for extended periods can easily cause irreversible damage.
3. Maintain a reasonable charge level during storage
It is recommended to maintain a charge level of 40%–60% during storage.
4. Reduce usage intensity in low-temperature environments
Battery capacity decreases at low temperatures, making deep discharge more likely.
5. Use a BMS with low-voltage protection
The BMS will automatically cut off power when the voltage approaches the lower limit to prevent over-discharge.
6. Regularly maintain batteries that are not used for extended periods
Check the voltage every 2–3 months and recharge as needed.
Part 5. How does Yizhan Electronics prevent overcharging and over-discharging from the source?
At the product design and manufacturing stage, Dongguan Yizhan Electronics has made safety control a core standard:
✅ High-consistency cell screening to reduce voltage deviation
✅ Intelligent BMS for precise control of charging and discharging thresholds
✅ Multiple protections: overcharge/over-discharge/overcurrent/overtemperature
✅ Aging test and function verification before shipment
✅ Support for parameter customization for different application scenarios
These designs not only improve safety but also significantly extend the overall battery life.
Part 6. Management Suggestions for Enterprises and End Users
Establish standardized charging and discharging operating procedures
Provide basic battery usage training for employees and users
Clearly state charging and discharging precautions in the product manual
Choose a reliable battery supplier with technical support
Scientific management is an effective way to reduce battery failure rates.
Part 7. FAQ: Common Questions about Charging and Discharging Management
Q1: Can the battery be charged to 100% every time?
A: Yes, but it is not recommended to use or store the battery at full charge for extended periods.
Q2: Does letting the battery drain until it automatically shuts down count as deep discharge?
A: Some devices have protection, but doing this frequently will still affect battery life.
Q3: Is it better to charge less often?
A: Reasonable shallow charging and discharging is actually more beneficial for extending battery life.
Q4: Can BMS completely prevent human error?
A: BMS can significantly reduce risks, but proper usage is still very important.
Q5: Does Yizhan Electronics provide charging and discharging usage guidelines?
A: Yes, we can provide customers with complete usage and maintenance advice.
Overcharging and deep discharging are the main factors affecting the lifespan and safety of lithium batteries. By adopting correct usage habits, reasonable storage methods, and choosing high-quality battery products with intelligent BMS, risks can be significantly reduced and service life extended.
Dongguan Yizhan Electronics Technology Co., Ltd. always adheres to the principle of “safety and reliability first,” providing customers with high-quality, customizable lithium battery solutions to help products achieve longer lifespan and more stable performance.