Check out this article, "Lead-Acid Battery Applications Drive the Li-ion Market", written for Electronic Design in February 2017.
The consumer market for Li-ion batteries is huge, but it is relatively flat. Predictably, a growing market for batteries is electric vehicles, but surprisingly, the biggest area of growth and adoption of new batteries is “everything else” from fork-lifts to ventilators. Sealed lead acid batteries had a corner on the market for 200 years, but that is finally changing thanks to Li-ion batteries that are more diverse in capability. This article compares and contrasts Li-ion and lead acid batteries, and this comparison will highlight the commercial/technical applications for Li-ion in traditional lead acid products. Additionally, this article reviews the considerations when using Li-ion battery technology to power devices that are designed to operate from lead acid batteries.