Inside a Battery

EGO_56VI wonder what is inside of a lot of items I see on a daily basis, but I really wonder if most other people think about what is inside the battery packs that are shipped with tools.  There is a lot of battery technology in the new Lithium Ion batteries that in some cases the consumer’s ideas of these batteries are stuck in the past where batteries did not last a long time and had very poor longevity.  With the new Lithium-Ion technology we see a lot of tools that are performing nearly as well as corded tools.

There are also new markets that are popping up due to the power and technology of these batteries.  Hybrid cars are now a reliable option for almost any user.  From there we have stepped into battery operated outdoor equipment.  While battery operated mowers might have been out for some time, the new ones are legitimate.  They have smaller batteries that can run long enough to allow you to finish your lawn on one charge.  The time it takes to charge these batteries have also come down in the last few years.  The old technology had the charge times from 8-12 hours whereas the new systems are down to 20 minutes in some cases.  All of this technology allows us to get jobs done with ease and also with less noise.  So let’s take a look as to what is inside one of these batteries.

Opening a Battery

EGO_56V_VentWhile sitting with some engineers from EGO, we came up with the idea to take a battery apart and show everyone the technology and workings of their battery pack and what makes them so special.  This technology has changed how many will take care of their yards for the rest of their lives.  This battery has taken around seven years of lab testing, technology upgrades and software tweaks to get everything working to get the user the not only the power they need but also the runtime to complete their yard.  The battery has to stay cool, take the shock of being dropped, handle vibration, and survive through getting soaked.

EGO_56V_DesignEGO has a battery that is U shaped so they do not have batteries stacked up in a brick.  They call this Lithium Arc Technology.  Layers of batteries mean layers of heat that cannot be easily removed from the housing that holds the cells.  So as your batteries work, they naturally get warm.  The trick is to keep them as cool as possible and not let them get over 60 degrees Celsius.  So EGO relies on their unique shape and venting to allow the battery to shed heat.  Beyond that, they also have a coating over each battery that has a chemical change as it gets warmer.  This wrap pulls the heat out of the battery as the cell gets warm and allows the battery to stay cooler.  This technology allows EGO to get over 2,000 charge and discharges per battery life in the lab.  That equates to 40 years of mowing the lawn for most people.  We aren’t saying you will get 40 years out of your batteries, but in the lab, they are able to see these results.

EGO_56V_WeldedEGO also has each of their cells in a roll cage so when the battery does get dropped, none of the cells can move and lose their connections.  The electronics are welded in place providing a solid electronic connection that resists vibration and other forces that could weaken a connection to one of the cells.  This set up makes the EGO engineers so confident in their design that they were tossing the battery packs around and dropping them on the floor.  While you might catch a gimps of it in our video, Barnaby actually throws a battery well over 10 feet.

EGO_56V_PottedOne of the last items each battery has to survive is water.  The circuit boards that control the battery packs are completely embedded (podded) in an epoxy type substance.  This prevents any water from coming into contact the brains of the battery.  Ego has even left some of their mowers out all year in the rain and snow and had the unit start up every time.

Inside each pack are multiple small lithium batteries that are set to make up the voltage of the battery.  They can also be set up to for higher amps at the same voltage, depending on how they are wired and how many batteries are in the pack.


While some of the technology in the battery sounds like common sense, much of it is not found in other brand’s battery packs.  So how do you know what is inside the battery packs you are buying?  You don’t and that is why we wanted to take this one apart and give you an idea of what is inside.  Stick with us as we continue to dive deeper into these tools and look at the technology that we are all purchasing.