The Expert Podcast

So as we've talked about before pretty soon electric vehicles will be a much greater percentage of the in-service motor vehicles than ever before right now it's approximate that one percent of on-road vehicles are electric vehicles and that is predicted to skyrocket in the coming years so if you are planning for future including electric vehicles how do you go about making sure that your ownership and your ownership costs are kept to a minimum well unlike a gasoline vehicle or internal combustion engine vehicle the vast majority of mechanical upgrades or maintenance comes from the battery the battery represents 40 to 50 percent of the cost of the vehicle unlike with a internal combustion engine vehicle that has multiple mechanical parts engine transmission drive line transfer case many other types of mechanical devices an electric vehicle has a few electric motors which are highly reliable electric motors last longer than the vehicle probably will and everything else is non-moving parts.
You know doors glass body panels those are basically um you know solid durable components the battery is where the highest cost comes from and where the maintenance or repair could come from and we're going to talk about what can affect the battery needing replacement or having a cost involved starts with this physics website where researchers have used x-rays to capture images of batteries degrading over time and this shows internally how and why a battery degrades and there's parts of a vehicle use which can change how fast that battery degrades because if that battery is degraded where it's not usable the car is out of commission just because of a battery the car is is not usable as a vehicle anymore unlike a regular gasoline vehicle your car battery is not a small box the size of a loaf of bread it encompasses the entire floor of the vehicle and it's not user replaceable you can't go to napa auto parts buy a new battery and pop it in and you're on your way the electric vehicle battery is an integral component of the vehicle chassis.
So these engineers looked at x-rays to show how the components of the battery were changing over time and it says that the materials in the battery crumble over time and the electrodes peel off inside itself so not only does it damage the battery but it can become a safety issue and there's ways that owners use vehicles that can accelerate this process so as a vehicle owner you want to make sure that you're using the vehicle in a way that doesn't degrade them and if you're purchasing a pre-owned or used electric vehicle you want to make sure that you can determine the history of the vehicle and we'll take a look at some of the tools you can use to determine that they're talking about how maybe they can change the coatings and make the batteries last longer but one of the most important thing is if you discharge to different levels that will affect the battery the biggest takeaway draining the battery a small amount causes less deterioration than draining the battery all the way so if you are an electric vehicle owner you don't want to run your battery all the way down to zero and then charge it back up you want to charge it as frequently as you can even if you're just topping it off from 90 percent to 100 or 80 percent to 100.
As we start replacing more and more combustion vehicles with electric it's really important to understand how batteries will behave under different conditions this is a good scientific research on how batteries work what does it mean in real life well one of the things that people could use electric vehicles for they're talking about the v2g process and that means vehicle to grid where people will take their electric vehicle plug it into the power grid and it will feed both directions meaning that you can sell charge from your vehicle back to the grid that's probably going to wear down your battery faster in addition there's a difference between calendar aging of batteries and cycle aging of batteries calendar aging refers to the battery just degrading by itself without charging and discharging when a battery is charged or discharged however it undergoes cyclic aging mechanical strain in the plating causes substantial deterioraging deterioration during the cycle so every time you you charge and discharge you're putting strain on the ions causing them to basically structurally degrade.
Then it talks about will vehicle to grid degrade your battery um utilizing a battery in v2g does not necessarily harm its performance it may even decrease it the main thing is going to be you don't want to drain it down to zero a daily drive cycle consumes 21 to 30 percent then discharging to the grid can minimize capacity fade so you don't want to drain it all the way and then charge it up all the way you want to use this to trickle charge and keep the battery healthy what about temperature one of the largest ev battery monitoring algorithms uses temperature ambient temperature around the vehicle to determine not only the range of the vehicle but also degradation so here's an example of a battery if you have a range of that vehicle of let's say 50 miles this is what is going to happen to the range at different temperatures here's your 100 range at this line right here if you are at freezing temperature 32 degrees you're only going to have a 30 or 80 percent range of that battery so you're only going to have 40 miles usable if you are down near zero you might have 50 of that range temperature of the outside world affects the battery and you go up on the other end if you start getting up over 100 degrees again you're back down to 80 percent.
Now most electric vehicles have built into them a heating system not only for the passenger and driver compartment but there is a heating system for the battery to keep it warm so you don't run into this problem the catch-22 is if you're heating the battery you're using electricity to heat the battery that electricity comes from the battery so by using that heater you're going to reduce the range that you have of that vehicle whether you're heating the inside of the car or the battery last but not least degrading the battery also is affected by heat vehicles operate in hot climates here is the baseline degradation over age and month so you know here's 120 months that's 10 years it's only going to go down it looks like two or three percent if it's in a hot climate and especially if you're using a fast charger it goes down 20 percent so hot climates and cold climates have an effect not only on the immediate range of a vehicle but also on the long term viability and durability of the main battery of the ev.
So from the same source it tells you some tips to preserve ev battery life this is crucial avoid keeping your car sitting with a full or empty charge you don't want to have it all the way full sitting for a long time or all the way empty for a long time keep your charge between 20 and 80 percent especially when you leave it for a long period minimize fast charging this is kind of counterintuitive to what people want to use it for dcfc is direct current fast charging some high use fast charging will need a faster charge but if your vehicle sits overnight charge it slowly the fast charge puts more strain on the battery so if you're going on a long trip and you have to stop somewhere to to recharge to get back on the road you have no choice but just remember every time you fast charge that vehicle according to these sources it's going to degrade the battery more more quickly even though climate you know you can't control the weather but if you are going to be very hot or very cold climates be even more careful about fast charging and extreme charging.
So using the vehicle is not a concern again this is not a mechanical internal combustion engine vehicle with a lot of moving lubricated components so driving the vehicle doesn't put much wear and tear on it it's the extremity of charging and the temperature and the headline of this of the story is this heat and fast charging is responsible for more battery degradation than age or mileage so unlike a vehicle that's a gasoline engine that you look right at the odometer to know how much life is left in the vehicle how many miles around the car that's the most important factor when you buy a used car on a vehicle that's a hybrid or electric vehicle that relies on the battery how many times it's fast charged and what the heat load or cold exposure on that vehicle in its history is more of a factor in how that battery is remaining.
And here's another representation of the battery this is underneath the floor of the vehicle so the vehicle is built around the battery you're not going to just swap out the battery there are some technologies where companies are looking at a quick battery exchange type technology we'll do some videos on that soon but that's not really in the pipeline for most vehicles yet the battery degradation tool assesses battery by five factors time high temperatures operation at higher low state high electric current and usage high electric current is these fast chargers that uses direct current charging for the battery and it's convenient because you can get back on the road quick but if you're gonna be parked overnight anyways don't use the fast charging technology let it trickle charge it'll be better for the battery and it will keep your vehicle viable for a longer period of time.