Do electric cars lose charge?

In Buyer's Guide, How-To Guides by evarchiveLeave a Comment

Yes, there are three types of charge that electric cars lose. The first is degradation over time from use of the batteries. The second is a slow drain when the car is not being used, this is also known as “Vampire Drain”. The third is temperature related when loss of charge occurs due to cold temperatures.

Battery degradation over time

Battery degradation over time is a fact of life for all of us. Do you remember how long your phone’s battery used to last when it was brand new? Well sadly if it is still not new you may have noticed that it runs out of battery quicker than it used to. Electric cars are the same, their battery degrades over time.

What is vampire drain?

Vampire drain sounds like a nightmare and it can be if you don’t take precautions. Imagine going to the airport and leaving your car in the car park and when you come back from your holiday, the car won’t start. Yes, the battery has been used up slowly while the car has been sitting in the car park.

Vampire drain can vary car to car, depending on the battery management system (BMS), the software installed in the car and the efficiency of the electronics. For example, Tesla’s have software that is programmed to turn on the air conditioning and keep the electronics cool if there are very high temperatures. This avoids any unnecessary damage to the electronics and saves people hassle in the long run. People can also connect to their car through the Tesla mobile app and access it to view the status of the car and view different information.

When the car hasn’t been used for a period of time it goes into a “sleep state”, which is similar to when your computer turns on its screen saver mode. Saving energy is the main aim of the game, a couple of miles difference can make a big difference to some journeys. Every time you go on your app to check or request information from the car it wakes it up which uses energy. I’m not saying you shouldn’t check your cars battery information and how much juice you have left, just be aware this uses some small amounts of energy. For other car makes I’m not sure how to save energy, but the following options below are handy if you’re leaving your car for a reasonable amount of time and going on holiday.

  1. Tesla energy saving should be turned on and always connected (next to energy saving) should be unticked (all of this found in the tab called “Display”).
  2. Range mode should be turned off (found in the tab called “driving”)
  3. Tesla sentry mode drains a lot of battery, turning this off will make your battery last longer.
  4. Leave your Car with as much battery as possible before you go on vacation.

Loss of charge through low temperatures

Batteries lose charge and range due to extremely cold temperatures, this loss of charge is lost temporarily until the batteries heat up to a more optimal temperature. Batteries can heat up through driving the car and it can also be heated up by using the battery heater option in the software settings (available in Tesla’s).

How to prevent loss of charge when temperatures are low?

Arrange it so your car is plugged in at a charger and that the charging finishes just before you want to go on your journey. This means that the batteries will be warm from charging and should be an optimal temperature, so you don’t lose range.

Another interesting thing to talk about is that your car will generally use more energy in cold weather. You will normally turn on the electric heating system inside of your car to keep you warm, this uses a lot more energy in comparison to an ICE car. This is because an ICE is typically inefficient and creates a lot of heat from the engine which is normally wasted energy, while as an electric car does not have this. The more efficient way to warm yourself is to use the heated seats, you are then heating yourself directly, rather than heating the air around you in the cabin which would take a lot more energy.

It is well documented about Nissan Leaf’s that certain models with a heat pump are really inefficient and reduce your range a lot. The models affected are the generation 1 cars (you can tell if it is Gen1 because there is no light in the charge port door) and the Visia (called this in Europe) which was a base model Gen2 Leaf.

Leave a Comment