Superior Battery Technology

Lithium-based batteries are the technology of choice for electric mobility applications. They store significantly more energy than all other batteries, they maintain a high current – a major advantage for electric drive systems – they do not lose their charging capacity, they supply power reliably even in the cold and have no memory effect. They also provide many more cycles than lead-based batteries.

Torqeedo has been a pioneer in the development of lithium batteries for boat applications for nine years. Since we make our batteries just a little bit better each year, we probably offer the most comprehensive and integrated protection and safety concept for lithium batteries on the market – coupled with performance and convenience.

Lithium Battery Safety

Besides performance, safety plays an important role for lithium batteries. In our view, five influencing factors need to be considered in order to ensure that safe really means safe:

  • Safe Battery Chemical Engineering A few years ago, when lithium batteries first started being used in propulsion technology, a number of vendors in some cases chose highly reactive chemicals such as lithium cobalt. However, they did not prove popular. Today almost all vendors use comparatively safe battery chemicals such as LiFePo or LiNMC – which Torqeedo has been using since 2005.
  • Safe, Individual Cell Packaging: Torqeedo only uses so-called safety cells, i.e. uses only welded steel cylinders each of which is equipped with multiple hardware safety mechanisms. Other forms of packaging such as foil-sealed cells (also called "coffee bags") offer a lower standard of safety as they afford less effective protection against internal short circuiting of the cells. (An exception here are cells with ceramic separators, which also provide safe packaging, but these are extremely expensive and very seldom used.)
  • Clean, Precision Production Processes on the Part of the Cell Manufacturers. The production process has a significant influence on the safety level of a lithium battery. This is why Torqeedo only uses cells sourced from the most reputable manufacturers in Japan and the USA.
  • Battery Management System (BMS) with Redundant Safety Features Unlike lead-based batteries, lithium batteries always need a BMS, which performs balancing and safety functions. If electronic components of the BMS fail, it can itself become a safety problem for the battery. For this reason, Torqeedo batteries are designed in such a way that a hardware fail-safe mechanism exists for each safety related component. Incidentally, this is also stipulated in the automotive industry, in aerospace and for medical technology.
  • Waterproof to IP67: Water in lithium batteries can lead to various problems such as corrosion of the BMS hardware or the creation of electrolytic gas. Lithium batteries on board a boat should therefore always be waterproof.