The Care & Feeding of Batteries on SV Apolima
30 May 2018 | Marshall Islands
Raining, almost everyday this week.
100 years ago a sailboat was much simpler than it is today. At that time boats were made of wood, canvas, galvanized rigging and Stockholm tar covered over with oil paint. Some had a small simple engine, usually hand started. Lighting was Kerosene lamps and candles. Navigation was DR supplemented with a good steering compass, a pelorus, paper charts, tide tables, a lead line for depth, a fog horn and maybe a patent log. For longer voyages a sextant with a Nautical Almanac and HO 249 tables. Many successful voyages were made in such basic (by modern standards) craft.
After a voyage there were chores and repairs. These usually consisted of sail repairs, chaff protection on all lines, adjusting rigging, painting, trimming the lamps wicks. These well built wooden boats were quite reliable as long as the running preventive maintenance was done on a regular basis.
Modern sailboats are another ‘kettle of fish’. Todays boat are mostly fiberglass which is strong and long lasting with minimal maintenance but other systems take more care.
Just about all have diesel engines for propulsion and generating electricity to charge batteries to power electrical and electronic devices such as: radios, SSB, TV, stereo, lighting, fans, computers, GPS plotters, depth sounders, Nav lights, autopilots, washer=dryers, anchor windlass, bilge pumps, inverters, refrigeration, water makers, weather fax, Satellite phone, and various other devices. These devices are by their very nature high tech electrical and electronic construction which do not do well in a salt laden environment. Most modern boats have high electrical demands which must be met by a well thought out system sized to handle the loads. These systems require constant monitoring and preventive maintenance.
It is said that modern cruising boats sail from port to port to replace and/or repair modern technology devices.
The heart of these systems is batteries. There has to be a means of storing electrical power which means having a batteries of a suitable capacity.
APOLIMA’s electrical setup:
• We have 4 six volt L16 wet cell batteries with a 840 amp rating. They are arranged in 2 banks but we run them on Both as one set.
• There is 4 solar panels for a total of 500 watts controlled by a Midnite Solar MPPT regulator.
• As we have an engine driven refrigeration compressor with holding plates that runs for 40 minutes a day it also charges house batteries with a 150AH alternator.
• An Ampair wind generator puts out about 30 amps/day in 10 kts wind.
• 3000 watt Inverter/charger.
Battery maintenance(wet cell):
▪ Keep batteries clean, well vented, topped up with distilled water to the proper level.
▪ Charge regularly to keep between 50 to 80+% charge.
▪ Check specific gravity with a battery hydrometer and log results regularly.
▪ To keep individual cells even they must be Equalized periodically. If the cells are not the same voltage, the higher voltage cells leak into the lower.
▪ keep battery cable connections clean and protected from corrosion. I use a copper infused product called Molyslip COPASLIP on all electrical connections.
To equalize on AV APOLIMA this is what we do.
▪ My procedure to equalize is to isolate one bank connected to the solar and the other as house use.
▪ Solar charges the one bank until the specific gravity of the acid peaks. At that point I select the Equalize setting on the MPPT regulator,
▪ Once the first bank is equalized the other bank is selected for equalizing.
Good battery care enables more reliable performance and longer battery life.