DIY: How to Winterize your electric fence battery

Winter Frau mit Handschuhen

Who is not familiar with the following situation? The first few cold days of the year – and your car is already struggling to start in the morning. Yes, when it comes to batteries, winter makes its own rules. What might seem like a cruel joke being played by Old Man Winter or Jack Frost is actually just simple science. Due to low temperatures, the chemical reactions within the battery are slow and therefore performance is limited. So, old, worn out batteries that have seen better days may stop working as temperatures drop. But what does this mean for your electric fence battery?

First things first

Before we go into detail, we can make a general declaration: The effect of low temperatures on electric fence batteries is no where near as big of a problem as its effect on car batteries. This is due to a couple factors.

  • Unless your animals will be grazing through winter, more often than not, the electric fence battery won’t be needed and simply needs to be stored. However, if your animals are grazing the whole winter, the possibility of a battery failure is obviously a serious situation. In this case, we recommend a solar powered electric fence energizer or (if possible) one with a direct current connection.
  • The power demanded from a car battery in contrast to an electric fence battery is far greater. Car batteries not only provide the initial high jolt of electricity to start the car, but they also stabilize the energy supply to keep the car running and power other things as well, like heated seats!

Of course this does not mean electric fence batteries do not need to be looked after in the winter months. Let’s look at a couple important steps for winterizing your electric fence battery.


The most critical point: avoid deep discharge

The main battery principle that you need to be aware of both for the active use of batteries as well as for their storage is: Avoid deep discharge!

Whether you use a lead, nickel or lithium battery, do not discharge the battery beyond the intended extent. A deep discharge can be recognized by the fact that the battery will drop significantly below the nominal voltage. Newer devices usually have a built-in under-voltage lockout, which functions as a deep discharge protection. The machine being powered is automatically switched off in time and the battery remains safe. Maybe you know this function from your mobile phone. There are now even electric fences with deep discharge protection. If your device does not automatically perform this function, you need to take care of it yourself!


Storing the electric fence battery correctly

Despite our example in the first paragraph, batteries are generally quite resistant to cold and often wear even slower in cold temperatures than in warm. So, storing the battery in a warm apartment (or house, or barn) is not recommended. The ideal location would be a basement or garage where frost protection is guaranteed but temperatures still remain a bit on the chilly side.

Batteries should also be in good condition and they should not sit longer than 2-3 months without being recharged. The chemical processes in the battery, which ensure that the required energy is provided, never entirely stop. If the battery is not used, it therefore discharges slowly with time itself. This is called self-discharge. In general, to avoid total discharge an unused battery should be recharged every 2-3 months.

  • Acid batteries

The older livestock owners among us remember the old batteries that had to be maintained by being refilled with distilled water or acid. Some of these batteries still exist today. We can extend the lifetime of these batteries by filling the liquid level (with distilled water) up to the specified maximum. It is especially important that these types of fence batteries remain fully charged during the winter months.

  • Dry batteries

Dry batteries should not be handled alone! Also, avoid touching dry batteries with your fingers or metal tweezers as this can cause them to discharge.

With these batteries, a full charge is not absolutely necessary. In Lithium batteries, the service life increases even if they are kept at a charge level of only 30-40%, however 60% is a best practice.

It is worth repeating because it is so important,: Avoid deep or total discharge in any case! It is far better to charge your battery a bit too much than too little.



To ensure that your electric fence battery survives the winter in good condition, you should

–   keep it cold (but frost resistant)
–   refill acid batteries to specified levels
–   fully recharge acid batteries
–   never refill dry batteries
–   charge dry batteries partially (I recommend about 60%)
–  to avoid deep discharge, recharge every 2-3 months