Prolonging Battery Lifetime

Electric fence batteries, when 12V is required, should always be a deep cycle or leisure type; car batteries should not be used. Leisure batteries are specifically designed to be discharged and recharged frequently, whereas automotive batteries are designed to give high power for a very short time. Using a car battery with an electric fence will simply kill the battery very quickly, making it an expensive option.

However, all batteries last longer if they are not fully discharged often, so it is important to know how long your battery is likely to last and try to change / charge it before it runs dead flat. Most battery energisers will automatically stop working when the battery reaches about 80% fully discharged, although we recommend trying to avoid letting the battery go below 60% to ensure maximum service life.

The table below shows typical figures and recommendations for the Hotline range of 12V batteries and fence energisers. Please bear in mind that battery performance can be affected by a number of different factors such as age and temperature; the colder the battery is, the lower it's capacity will be, meaning you will need to charge it more often.

Energiser
Power consumption 
(Cmax in A)
Maximum operation (days)*
Recommended charge cycle (days)
32Ah 12V Battery
75Ah 12V Battery
110Ah 12V Battery
32Ah 12V Battery
75Ah 12V Battery
110Ah 12V Battery
P250/S
0.040
30
70
103
20
47
69
P450/S
0.055
22
51
75
15
34
50
HLC40
0.100
12
28
41
8
19
28
P500
0.125
10
23
33
6
15
22
HLC80
0.133
9
21
31
6
14
21
HLC120
0.217
6
13
19
4
9
13
P525
0.250
5
11
17
3
8
11
* Most 12V energisers will switch off when the battery capacity reaches 20% due to voltage loss.
** This ensures that the battery does not fall below 60% discharge and extends service lifetime significantly.