Choosing the right battery significantly prolongs its service life
Choosing a battery for an energiser may seem like a difficult task: there are so many options... A few related tips can save you the trouble of constantly rummaging through stores.
For example, there are many types of lead-acid batteries commonly used with energisers. Vehicle starter batteries are often the most familiar. Another common battery type is the so-called leisure battery intended for low-current applications such as caravans and boats. There is a slight price difference in favour of the vehicle starter batteries, which are a tad cheaper.
Battery tips in a nutshell:
- Instead of a starter battery, choose a leisure battery to run the energiser.
- Charge batteries as soon as they become half-full.
- Remember to charge a battery regularly even when not in use.
- In winter, do not store batteries in unheated premises.
Leisure batteries are better suited for running a fence energiser than starter batteries
We specifically recommend using leisure batteries as an energiser’s power source. They are suited better as energiser power sources than vehicle starter batteries for a number of reasons. Firstly, leisure batteries can be discharged to a fairly low level over a long period of time without their capacity suffering. After all, this is how an energiser is mostly used: quite often, it just waits there at the edge of a pasture and is charged only when the power runs low (or when someone remembers about it). Secondly, a good leisure battery can provide up to twice the operating time on a single charge in low-current operation compared to a vehicle starter battery of the same size. When used in an energiser, its service life is always longer than that of a comparable starter battery. In other words, the slightly higher purchase price will pay off in terms of a clearly longer service life! As a further tip, batteries intended for use with solar panels are the best choice for solar panel energisers, and nowadays such batteries are quite readily available.
Starter batteries, on the other hand, have been made for momentary supply of high current and should be kept fully charged at all times. Because of this, they are ill suited as a power source for energisers. Honestly, who would take the trouble to keep the energiser battery at the edge of the pasture fully charged day in, day out? In practice, a vehicle starter battery can, of course, be used with energisers, but in this case, it is good to bear in mind that using a starter battery for low current supply over a very long period of time will cause internal destruction of the battery (so-called sulphation). If the vehicle starter battery is discharged too deeply, it could be damaged to the point where recharging could become impossible. Furthermore, starter batteries self-discharge quickly, sometimes even faster than the power consumption of a low-power electric fence energiser. In order for a starter battery to last as long as possible, it needs to be charged well before it becomes discharged, at least every month (so-called maintenance charge). The service life can also be extended by using a smart battery charger that performs battery maintenance during the charging process.
Do not forget to charge batteries even when they are not in use
After all, it often happens that the battery energiser is only used during the grazing season, and at other times of the year, the battery simply lies forgotten somewhere at the back of a cold storage shelf. By the way, this is an excellent approach if you like buying new batteries every spring! This might come as a surprise, but a battery also needs to be charged when the energiser is not in use to prevent battery damage caused by self-discharge. Even though storing a battery in a cool place is good for it, in extreme cold the battery can be damaged by freezing (the lower the battery charge, the more easily this happens). Therefore, in winter, batteries should not be stored in completely unheated premises. Batteries do not like heat either: excessive heat causes batteries to age.
Even though Olli battery energisers feature a deep discharge protection function that protects the batteries from being completely discharged, the service life of batteries used in energisers can be extended considerably by charging them regularly before the energiser’s deep discharge protection cuts off the power. Self-discharge and low battery sulphation also affect leisure batteries, but to a clearly lesser extent as compared to starter batteries. Therefore, to maximise the service life, leisure batteries should also be charged as soon as they become half-full.
What should the battery capacity be?
How do you know how long a battery will last? It depends on: a) the battery capacity (stated in ampere-hours, Ah), and b) the power consumption of the energizer (stated in milliampere-hours mAh, the respective information can be found on the energiser's packaging and here on the Olli website under the data of the respective energiser). The maximum battery life (in hours, h) can be estimated as follows:
Divide the stated battery capacity (e.g., 60 Ah = 60,000 mAh) by the energiser's stated power consumption (e.g., 100 mA): 60,000 mAh / 100 mA = 600h = 25 days.
However, it should be kept in mind that the power consumption of many energiser models varies depending on the energiser power setting and/or the load on the fence. Naturally, this also affects the battery service life.
The start of the next grazing season can be made easier, at least as far as the power supply is concerned, by choosing the right battery and ensuring proper battery maintenance and storage. The energiser will do its job if there is enough power! :)
P.S. Make sure that the energiser and its battery are always placed so that they are out of reach of animals and never come into contact with water. It is also a good idea to protect the battery using a battery box designed for this purpose. These boxes can be purchased at the same places as batteries and the most affordable ones only cost about a tenner or two.