Is my lithium battery damaged? As battery technology becomes more popular it is a question that crops up more frequently.
Indeed, the price of lithium battery tech is going down while durability is increasing. Additionally, the association between lithium batteries and Battery Management Systems (BMS) means that they are more safe and reliable than ever before.
However, battery faults can and do happen.
If your battery is not performing as well as it did when you first bought it, you might wonder – is my lithium battery damaged?
There are 5 warning signs that your lithium battery is damaged:
lThe capacity is reduced
lThe voltage is low
lThe self-discharge rate is high
lThe battery is overheating
lThe battery is bloated
This article will answer your most asked questions about damaged lithium batteries, and how you can properly take care of your battery to extend its life duration.
How can you damage a lithium battery?
There are currently two types of lithium batteries fitted for solar energy storage: LiFePO4 and LTO. They are robust and durable.
The newest LiFePO4 batteries are certified to last 10 years or 5’000 cycles, and some manufacturers are offering 5-year warranties.
LTO batteries are even more durable with up to 30,000 cycles (80% capacity retention) and 25 years of life.
Moreover, they both include a BMS (battery management system) that regulates the charge/discharge steps, and equalizes and protects the battery cells by monitoring the temperature and voltage.
The BMS can cut off each battery cell when it detects values above the fixed limits.
Despite their durability and the protection offered by the BMS, several factors could damage your lithium battery:
External Environmental Factors:
lHeat: temperatures higher than 140°F
lCold: for LiFePO4 batteries below -4°F
lWater/air humidity
lPhysical damage (shock)
Internal Factors:
lOver charging above 16.5V for a 12V battery
lOver discharging below 10V for a 12V battery
lManufacturing defects
lLow-quality components
What happens if your lithium battery is damaged?
If your lithium battery is damaged multiple events can take place These events are categorized according to the extent of their risks:
Lower-risk events are related to the degradation of the battery performances:
lLow voltage
lLow current and in the end a lower capacity
These events are not a threat to the user but should be monitored.
Higher-risk are as follow:
lFire or explosion of your battery
lLeakage of the electrolyte (toxic and flammable)
Lithium when in contact with water (even air humidity) is extremely reactive and could catch fire. Overheating, overcharging, and shocks also promote thermal reactions inside the lithium battery.
What are the warning signs that my lithium battery is damaged?
There are multiple warning signs that can tell you if your lithium battery is damaged.
Some of them are quite alarming, others would only be the sign of normal degradation over time.
The least alarming warning signs are related to the battery performance, and should not be a concern for your safety:
lThe voltage is low
lThe battery capacity is reduced
lThe self-discharge rate is high
The most alarming warning signs are related to the physical appearance of your lithium battery and are definitely a threat to your safety:
lOverheating battery
lSwollen battery
lThe battery has an unusual smell
lThe battery is discolored
If you detect one of the most alarming signs, we strongly advise you to immediately disconnect the lithium battery and store it in a very well-vented area, far from other batteries and potential ignition sources.
Can you repair a damaged lithium battery?
First of all, let's have a quick look at the major components of a lithium battery.
The latest lithium batteries consist of:
lBattery casing, usually ABS (Acrylonitrile Butadiene Styrene) plastic
lPrismatic Lithium battery cells
lBattery management system (BMS),
lConnectors (bus bars, wires…)
All these components can be bought separately in specialized battery stores and also on Alibaba.Repairing your lithium battery is possible but you should be extremely cautious and follow the safety rules.
lFirst of all, if you detect one of the more alarming warning signs previously mentioned, your lithium battery cannot be repaired and should be handled with maximum care. We advise you to bring it to a battery store. They will take your battery to a recycling
lIf you only detect the least alarming warning signs, you will be able to fix your lithium battery either at home or with the help of a battery specialist.
lThe battery specialist will evaluate the degradation state of all your lithium battery components and more specifically your BMS and the prismatic lithium battery cells.
lThey will measure the voltage and capacity of each prismatic cells by applying a power load and a charging current. If one or more cells are underperforming, they can be replaced.
lThen they will test the BMS, as most of the time, lithium battery failures are due to a defective BMS. The BMS response to a power load and a charging current will be evaluated as well as its capacity to equalize multiple battery cells.