Battery maintainers for commercial vehicles and stored fleets
A battery maintainer is not the same as a battery charger. A charger delivers a fixed current to bring a discharged battery back to full charge, typically in a few hours. A maintainer monitors battery voltage and delivers a small, controlled trickle charge to hold the battery at optimal state of charge over extended periods. Left on indefinitely, a quality maintainer will not overcharge or damage the battery.
For commercial vehicles that stand between assignments, seasonal-use plant, and fleet vehicles with irregular usage patterns, a battery maintainer prevents the gradual self-discharge that leads to a flat battery on a Monday morning. Modern intelligent maintainers also perform a desulphation cycle - applying a higher-voltage pulse to break down lead sulphate crystal build-up on the battery plates - which extends battery life in vehicles where regular use cannot prevent periodic deep discharge.
Frequently asked questions
What is the difference between a battery maintainer and a battery charger?
A battery charger delivers a high current to charge a flat battery back to full state of charge quickly. A battery maintainer monitors battery voltage and applies a small float charge to keep a fully charged battery at optimal voltage over extended standing periods. A maintainer will not damage a battery left connected long-term; a standard charger will overcharge and damage a battery if left connected after full charge.
Can I use a 12V battery maintainer on a 24V HGV system?
No. A single 12V maintainer cannot be connected directly to a 24V battery system. To maintain a 24V system, use a 24V-specific maintainer or connect two 12V maintainers - one to each 12V battery in the series pair.
How do I know what capacity battery maintainer I need for my vehicle?
Battery maintainers are matched to battery capacity, expressed in amp-hours (Ah). HGV batteries are typically 150-200Ah per unit. Check the maintainer's specified battery capacity range against your battery specification before connecting.
Will a battery maintainer recover a completely flat battery?
Most maintainers will not charge a deeply discharged battery from flat. If the battery voltage has dropped below around 3V per cell - 6V on a 12V battery - a standard maintainer may not be able to initiate a charge. Use a full battery charger to bring the battery to a partial state of charge first, then switch to the maintainer for ongoing conditioning.
