Application Notes
Back to Resources

Observing the Surface Condition of Separators in Lithium-Ion Batteries Using a Scanning Probe Microscope (SPM) Combined with a Laser Microscope

Separators in Lithium-Ion Battery
Separators in Lithium-Ion Battery


Li-ion battery cells contain separators, which are porous films made of polyethylene, polypropylene, etc. The separators provide a barrier between the cathode and anode that prevents short-circuiting in the battery. If material failure in a battery cell causes its temperature to rise above a predefined limit, the film dissolves, and the pores that normally allow Li-ion to pass through are closed. This stops battery charging and discharging, prevents a further rise in temperature, and eliminates the risk of an overheated battery or fire.

It is important to accurately evaluate the condition of separators to ensure uniform film thickness and similarly sized, evenly distributed pores. A good separator surface condition allows Li-ion to move smoothly, which enables the efficient flow of electric current.


The LEXT OLS4500 is a laser measuring microscope that combines laser microscopy with scanning probe microscopy (SPM) functionality to accurately observe and measure film thickness uniformity and the size of pores.

LEXT OLS4500 product features

(1) Enables seamless observation and measurement using both a laser microscope and SPM on the same area of a sample.

(2) A laser microscope improves productivity when obtaining final SPM data.



A bright-colored area in the laser microscopic image indicates that the area is high, while a dark-colored area indicates that it is low.

The laser microscopic image makes it easier to identify the area you want to observe with the SPM.

Olympus IMS

LEXT OLS4500 is Nano Search Microscope which is combined a laser microscope and scanning probe microscope (SPM) in the same instrument to allow observation and measurement over a wide range of magnifications (from around 50x up to 1,000,000x)
Sorry, this page is not available in your country
Let us know what you're looking for by filling out the form below.

This site uses cookies to enhance performance, analyze traffic, and for ads measurement purposes. If you do not change your web settings, cookies will continue to be used on this website. To learn more about how we use cookies on this website, and how you can restrict our use of cookies, please review our Cookie Policy.