There are no mysteries about our deep-cycle, lead-acid batteries. Our success lies in our attention to detail, and sales volumes that allow us to set affordable prices. We wish we could say the same for the secrets inside lithium-ion batteries.
Hidden Lithium-ion Battery Secrets
Competition is tight in the lucrative lithium-Ion battery market. Leading manufacturers keep their tweaks away from their competition. The bottom end of the market hides its short cuts inside battery cases, that they paste over with false promises.
Lumafield are engineering consultants, helping manufacturers improve the quality of their products. They have refined medical cat scan technology, to peer inside lithium-ion cases without disturbing the contents. They appeal to us not to take chances and open these cases ourselves, because this can be dangerous.
Peering Inside Lithium-Ion Chemistry Safely
We need to be extra careful when we investigate the secrets inside lithium-ion batteries. This is because they store much more power than alkaline alternatives, even when they appear to be discharged. Lumafield used their refined technology to examine a battery cell safely from a popular make of electric car.
Their observations were most interesting. From the outside, the LG21700 lithium-ion battery cell resembled a household alkaline battery. However, once they peered into the cell using a computed tomography CT scan, they immediately noted these significant details:
- There were two tabs spot-welded to the negative end of the case, leading into the battery and acting as the anode.
- These tabs extended deep into the lithium-ion battery, providing a large surface highway for electrons.
- Lumafield also spotted concentric layers of material rolled tightly and inserted into the cylindrical battery case.
- They counted 25 of these layers, each with a negative and a positive side, and a separator between.
- Finally, they noted a cathode in a gap in this concentric roll, connecting to the positive end of the battery case.
This layered structure delivered excellent storage density. However, as Lumafield notes, it was fragile. Damaging a single layer could cause the battery to short out, they warn, and release immense heat inside.
The electric vehicle battery cell that they examined had a stout metal case. However, as Lumafield continues, “lithium ion batteries are often packed in thinner, less-protected enclosures in phones and cars …”
More Information
The Dangers of Lithium-ion Batteries
Predicting Lithium Intercalation Rates
Preview Image: What’s Inside a Lithium-Ion Battery
