Boat batteries in Málaga

Starter, house or dual purpose: what each one does

• Starter: delivers a lot of current for a few seconds to crank the engine. It is not built for deep discharge: run the fridge or the electronics from it with the engine off and you shorten its life.
• House (deep cycle): supplies a small current for many hours to the fridge, lights, fishfinder, autopilot or bilge pump, and withstands many discharge and recharge cycles.
• Dual purpose: starts the engine and also tolerates moderate cycling.

When is one dual-purpose battery enough? On inflatables, small open boats and craft with few electronics, where there is only room and weight allowance for a single battery. As soon as you spend nights at anchor or carry a fridge, the sensible approach is to split the circuits: one battery kept for starting and a separate house bank, so the engine always starts even if you have run the house bank flat.

House bank capacity: a rough guide

The amp-hours (Ah) of your house bank depend on what you use between charges, not on the length of the boat. These ranges are only a starting point.

Work it out from your real consumption. Add up what each item draws (amps multiplied by hours of use per day). With lead batteries it is best not to go below 50% charge, so the installed capacity should be roughly double what you use between charges; with lithium a larger share is usable. The windlass and bow thruster draw a very high current for a short time and are normally used with the engine running: their battery and cabling are sized separately.

AGM, EFB, flooded lead-acid or lithium on board

• AGM: sealed, maintenance-free and with the electrolyte absorbed, so it does not spill when the boat heels and it stands up well to vibration and slamming. It gives off hardly any gas in normal use. Limit: it does not tolerate overcharging and needs a charger with an AGM profile.
• EFB: lead-acid with liquid electrolyte, reinforced to cycle more than a conventional battery. A good dual-purpose choice when the budget is tight. Limit: it must be fitted upright and in a ventilated compartment.
• Flooded lead-acid: the classic choice for starting. Limit: it gives off hydrogen while charging, so the compartment must be ventilated; it cannot take steep angles and it is damaged if left discharged.
• Lithium (LiFePO4): far lighter, accepts deep discharges, lasts many more cycles and charges quickly. Limit: it requires a compatible charger, alternator and protection devices, and is generally used for the house bank rather than for starting the engine.

Marine battery ranges in our Málaga catalogue

Our online shop has Varta and Optima product pages with dimensions, capacity and cranking current. These are the ranges, with a few specific models:

• Varta Professional Starter (starting, lead-acid): for cranking the engine. For example, Varta LFS74 12V 74Ah 680A and Varta LFS95 12V 95Ah 800A.
• Varta Professional Dual Purpose EFB (dual purpose): starting and moderate house use in a single battery. For example, Varta LED95 12V 95Ah 850A and Varta LED190 12V 190Ah 1050A.
• Varta Professional Dual Purpose AGM (dual purpose, sealed): for boats with more electronics or with batteries in poorly ventilated spaces. For example, Varta LA105 12V 105Ah 950A.
• Varta Professional Li-Ion Deep Cycle (12.8 V lithium for house use): far less weight on board. For example, Varta LL100 12.8V 100Ah.
• Optima Blue Top (spiral-cell AGM): highly resistant to vibration, with a starting version and a dual-purpose version. For example, OPTIMA BTSLI-4.2 12V 50Ah 815A (starting) and OPTIMA BTDC-4.2 12V 55Ah 765A (dual purpose).

You will find every model in the boat battery catalogue. For large house banks and deep cycle we also supply Trojan, Rolls and TAB on quotation: tell us the voltage, capacity and space available. We also sell Tudor and Exide.

Delivery to marinas on the Costa del Sol

We deliver batteries to marinas in Málaga and along the Costa del Sol, to private owners and to trade customers alike. It is delivery only: we do not fit the battery on board. We bring it to the marina and you or your marine engineer connect it. Ask about delivery times at battery delivery to marinas.

If you would rather come in, we are at C/ La Orotava, 100 (San Luis industrial estate, Málaga), with no appointment and on a first-come, first-served basis. Bring the old battery and we will test it free of charge. We keep the used battery and recycle it at no cost: please do not leave it on the pontoon or in a marina skip.

Maintenance in a coastal climate: salt, terminals and winter lay-up

The salt air and heat of the Málaga coast shorten the life of any battery. Four habits make the difference:

• Clean, protected terminals: salt corrodes the connections and adds resistance. Clean them, tighten them and protect them with terminal grease or spray.
• Battery firmly secured: strapped down in its box, so it does not move in a swell. On small outboards, moreover, the engine charges very little: we cover it in which battery an outboard engine takes.
• Never left half charged: a lead battery that spends weeks discharged becomes sulphated. Recharge it when you return to port. If you are considering lithium for more cycles, first read lithium on board.
• Winter lay-up: if the boat will be idle for months, leave the battery charged and disconnected or on a maintenance charger. The details are in how to winterise your boat battery.

Do you have a jet ski as well? It takes a different, motorcycle-type battery: see jet ski and personal watercraft batteries.