Infinte Batch Loop during Batch export of Webform Submissions with background_batch

We want to export webform submissions for certain webforms each day. To achieve this we use hook_cron. As webform_results_export is deprecated we use webform_results_export_batch and process the batch with the background_batch module.
The webform_results_export_batch sets some default options in the batch-array (range_type, components, .... - see function webform_results_download_default_options). But range[batch_size] option is no default option. This leads to a problem in the function processing the single batch rows. As ceil($context['sandbox']['sid_count'] / $options['range']['batch_size']) always evaluates to INF the 'batch_max'-Option also is INF and the batch-process will never finish.