How to extend your existing boat battery with lithium

Connect a lithium to a lead-acid battery system? Yes, you can! LE300 Smart Battery System is full of innovative hybrid functions and allows you to add what you want while you keep what you have.

Choosing between a lead-acid battery and a lithium system can be tough. Both have their pros and cons. While lithium requires less space and weight for the same storage capacity, it is complex to install and does not function well in the cold. Plus: It requires a high initial investment. Lead-acid batteries are affordable and simple. However, they are also heavy and tend to have a short life span.

For all those who would love to have the best of both, there is good news: You can! LE300 Smart Battery System is a plug and play lithium extension for existing 12 V lead-acid battery systems (that includes AGM and gel). Simply connect the battery cables to the positive and negative poles of your current battery and that is it. No programming, no changes to the electronics. It takes a couple of minutes.

The plug and play installation of LE300 can be done within minutes
(Image rights by Bertel Kolthof via Zeilen Media B.V.)



What you get: More capacity and even more unique features. For example, an extended lifespan of your lead-acid battery by up to ten years. LE300 will also keep it fully charged during winter, even in standby mode. With the right lithium-lead ratio, you can simply forget about batteries during the cold months and get back on the water in spring.
LE300 is modular and scalable: You can combine as many of the 28 Ah modules as you want. Well, up to 24 of them. More than enough even for long excursions. The good thing: You can adapt your capacity whenever you need it. You could start with one or two for example and add more next year – just as you need and as your budget allows it. The German manufacturer BOS AG recommends a minimum of one module per 100 Ah of lead-acid battery. Each module of LE300 weighs 3.4 kg. Thus, they even fit into small boats.

Six modules of LE300 connected to a lead-acid battery.

Pricewise, the fact that you can simply keep using your existing battery plus charging technology is a plus. It means that for the total usable battery capacity, the price per ampere-hour is significantly lower than in pure lithium systems. Simply because you already own a part of your total capacity. And why throw out what still works? Keep what you have and add what you want, that is the core principle.

By the way: This is also useful if you are thinking about an additional lead-acid battery. It is not recommendable to connect new lead-acid batteries to used ones. With LE300, you do not need to replace the existing battery to get more capacity. Just install the lithium modules.  

Hymer Smart Battery System training

Hymer Smart Battery System training

Sales can be great fun – this is what our team members Daniela and Dominik experienced in the past weeks. In Italy and France, they have successfully trained numerous Hymer partners. A mission, which was not only successful but also highly enjoyable.


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