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Technology trend: Tabless contacting in small-format lithium-ion cells

26. May 2026

An increasing number of cell manufacturers are producing small-format battery cells using the so-called tabless design. Within Omnitron Griese’s product portfolio, too, this cell architecture—which does not require traditional tabs—currently accounts for a small but growing proportion. This applies, for example, to the 18650, 21700 and 26650 formats frequently used in battery packs. But what lies behind the trend towards ‘tabless contacting’ in small-format lithium-ion cells? And what improvements does it drive?

Advantages: charging time, efficiency and service life

Tabless technology was originally developed for larger cell formats in the e-mobility sector. Today, small-format tabless cells are also in use, for example in power tool batteries, e-bikes or other high-power applications. “The tabless design has a positive effect on the cell’s internal electrical resistance,” says Dr Frank Diehl, Chief Operating Officer at Omnitron Griese GmbH. This effect offers several advantages. Due to the lower electrical resistance, less heat is generated, the cell can charge faster and deliver higher power. This increases the cell’s efficiency and service life.

The reason for the improved cell properties lies in the redistributed current flow. In a conventional cell design, metal tabs attached at specific points conduct the current from the electrodes to the terminal. This results in long paths within the cell. Furthermore, the current ‘backs up’ at the few junctions. In the tabless design, the metal tabs are omitted. Through direct contact between the electrode and the housing or terminal, the current is simultaneously conducted along the entire edge of the winded electrode.

Challenges: Improving in relation to the format

The improved conductivity and the resulting higher currents do not, at least so far, have an universally positive effect across the board. “Compared to conventional cells, tabless formats are still significantly more expensive today,” says Dr Frank Diehl. “The existing production lines in the cell industry, including their machinery, processes and testing technology, are still designed for the tab design. The switch requires an investment that has yet to prove its worth, particularly for smaller cell formats.” The reason: the improvement in cell performance achieved through the tabless design is less pronounced in small battery cells than in larger cell formats. “The current paths are already relatively short here. As a result, the tabless architecture delivers proportionally less in small-format cells,” says Dr Frank Diehl. “Furthermore, not every application requires new high-end performance; that is also something to bear in mind.”

Decision-making: current profile, space consumption, thermal requirements

The ongoing expansion of the Omnitron cell portfolio to include further tabless formats is nevertheless a real asset – both for the direct users of the cells and for customised battery packs. “The growing portfolio gives us greater flexibility in the development of battery and battery pack solutions, enabling us to meet customer requirements even better. Essentially, we are cell-agnostic pack developers. We seek out the best options for our customers. To do this, we need a broad cell portfolio comprising different formats, chemistries and, indeed, architectures,” says Dr Frank Diehl.

“If, at the same cost, we can contribute more reserves to the service life whilst also achieving a better thermal effect, then our choice naturally falls on cells with tabless contacting. Tabless technology is also always an option when energy density and power density are important in an application.” This holds true across industries, for example to applications with high inrush currents or those requiring continuous operation or even an uninterruptible power supply (UPS). Here, the tabless design achieves higher discharge and charge rates. This means that the cells charge faster whilst maintaining the same energy density. “Even where space within the pack is limited, the tabless design is likely to come out on top,” says Dr Frank Diehl. The choice of cell design is therefore always based on the current profile as well as spatial and thermal requirements. Only once the application requirements have been met does the question arise as to whether the cell design should aim for higher performance or cost optimisation.

Future developments: lower unit prices through industrial scaling

No major innovations in tabless technology are expected in the future. “The leap in performance has been achieved with the switch from tab to tabless design,” says Dr Frank Diehl. “Technologically, the design will certainly only evolve gradually from here on. However, it is very likely that tabless-format cells will become cheaper over time.” The cell industry is clearly on the path to transitioning from tab design to tabless design. More and more manufacturers are planning the mass production of small-format tabless cells. In doing so, they are following a clear technological trend which, although it has not yet achieved a widespread market breakthrough, has clearly established itself in the product and its application. This will drive industrial scaling. “Mass production can lead to comparable or even lower unit prices despite the consistent cell cost drivers,” says Dr Frank Diehl. “How quickly and how completely this transition will take place remains to be seen. In some cases, patents are slowing down the rapid spread of tabless solutions. And, not least, customer demand determines the market. As long as there are still tab production lines in operation, there will also be cells with traditional tabs. After all, they are easy to manufacture, inexpensive and tried and tested.”