*1.2. Battery Content and Battery Composition*

In Austria, the collection rate for portable batteries sank from 55% in 2015 to 45% in 2017 and it has stayed on that low level ever since [6,7]. A lot of the batteries that are not collected properly are falsely disposed in different municipal solid waste fractions [5]. Material flow analysis revealed that: (1) about 718 tonnes end up in residual household waste, (2) about 41 tonnes in lightweight packaging waste, and (3) about 17 tonnes in metal packaging waste.

For material flow analysis (MFA), [4] investigated the battery content and battery composition of the following waste streams: (1) residual household waste, (2) lightweight packaging

**Citation:** Nigl, T.; Baldauf, M.; Hohenberger, M.; Pomberger, R. Lithium-Ion Batteries as Ignition Sources in Waste Treatment Processes—A Semi-Quantitate Risk Analysis and Assessment of Battery-Caused Waste Fires. *Processes* **2021**, *9*, 49. https://doi.org/10.3390/ pr9010049

Received: 30 November 2020 Accepted: 24 December 2020 Published: 29 December 2020

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waste, and (3) metal packaging waste. In addition to the quantitative weight-related values for MFA, particle-related data were published in [4] and they are given in Table 1.

**Table 1.** Particle-based data for portable and lithium batteries in various municipal waste streams (data from [4]).

