Why you can't choose a cheap lithium battery?
26 Aug 2021
As lithium batteries have grown in popularity, they have inadvertently created a significant issue that could rob consumers and businesses of thousands of dollars.
Fuelled by a lack of regulation by Global Standards, a technology that is widely misunderstood and globalised has allowed battery cowboys to import cheap, inferior products that are faulty and potentially dangerous.
These products understate the usable capacity and are sourced from manufacturers with questionable procedures and parts in their construction, in some cases even using second-hand or low-grade cells.
Understandably, consumers are hesitant to lift the lid on their battery as this would void the warranty of a product (we recommend you never dismantle a battery case). However, with a recent picture circulating on social media, it has exposed a shocking truth to what is in a cheap lithium battery.
Cheap lithium batteries are very dangerous and can cause serious accidents, threatening personal and property safety.
Reasons of cheap lithium batteries:
1. Use the Lithium automotive Battery retired from electric vehicles, these lithium batteries are usually attenuated to 70% of the rated capacity, the internal materials like active material, separator etc. have been aging a long time, the life is unpredictable, and it is easy to short-circuit and cause battery fault, have risk of fire and explosion.
2. Use grade B lithium batteries cells, which have some defective at the factory, these battery cells are very cheap, poor consistency, and have poor cycle life.
3. Use the cheap battery cell, which use low quality electrode material (500cycle life, 1000cycle life etc. rather than 3000 cycle life), separator and electrolyte.
4. Use cheap BMS (battery management system) which have cheap MOSFETs and Capacitors, overheated and melted, potentially causing fire and damage to any electrical component connected to the battery, including the host device.
5. The bus bar uses a cheap bus bar, the cross-sectional area is not enough, the rated current cannot be passed for a long time, and the heat is serious.
6. The cable used cheap material, without safety test and certification, and this cable is likely to be inadequate for the current passing through it. Further restricting power and generating more heat.
During high-current discharge, the cable will heat up severely, causing the PVC shell to melt and catch fire.
7. Use moisture has penetrated the case, from either poor sealing or user abuse, which would allow rust to develop internally. This can lead to a higher internal resistance that restricts power and generates heat.
8. The low quality connectors, could cause shorting.
9. Overall poor construction of the case, which could lead to the cells coming loose from even small vibrations.
“It’s important to remember that Lithium Iron Phosphate (LFP) is different from other lithium chemistries and is actually a really safe and reliable technology, but when a (generic) product like this is released to market it has potential to damage its (technological) reputation,”
A user should also be wary of international suppliers, as consumer law does apply to the retailer when supplying goods. If a company has an influx of genuine warranties, they would be obliged to provide a refund or replacement. If those warranties are not being honored from the manufacturer to the retailer, this could put their business at significant financial risk.
WHAT TO LOOK FOR
To avoid disappointment, only buy from a reputable business or supplier like EverExceed and arm yourself with knowledge and a list of questions that verify the quality of the product.
Considerations include:
• The BMS should protect against short circuit, high voltage, and low voltage, high current and high/low temperature.
• Achieved an UL, IEC Certifications of some sort and ideally covers the whole battery or at very least the cells. This guarantees the safety, reliability and claimed capacity of the battery.
• Always ask for spec sheets.
• Be aware of your system’s needs and compare to the battery. If these do not match, speak to the supplier.
