Marine Electrical and Electronics Bible: a practical handbook for cruising sailors, fourth edition
by John C. Payne 22 Dec 2023 13:08 PST
Marine Electrical and Electronics Bible is a useful and thoroughly practical guide that explains in detail how to select, install, maintain, and troubleshoot all of the electrical and electronic systems found on board cruising, racing, and trawler yachts, power- and motorboats, and even superyachts.
This guide is fully illustrated throughout with more than two hundred charts, wiring diagrams, tables, and graphs.
Light on theory and heavy on practical advice, Marine Electrical and Electronics Bible recognizes that most cruising yacht owners do not have a technical background. The chapters are formatted to enable quick access to technical descriptions and troubleshooting advice. They are also infused with the author's own professional marine electrical background and lived cruising experiences, along with lessons learned over decades of continual input and conversations with fellow sailors.
Praise for previous editions
"If you are mystified by all those wires, fuses, buttons, switches, etc., this could be your ticket to understanding not the last word, but the latest." — WoodenBoat
"This encyclopedia begins with primary ship systems, like battery, water, engine and AC, before progressing to more esoteric navigational, communication and instrumentation systems. Laid out like an extended outline, this is, perhaps, the most easy-to-follow electrical reference to date, complete with worldwide service contacts." — Cruising World Magazine (US).
About the Author
John C. Payne is a professional marine electrical engineer and surveyor, with a career spanning more than forty years in commercial shipping, the offshore oil industry, and yachting. He is a qualified technical writer and author of fifteen marine electrical and electronics books and numerous magazine articles. John has been involved with everything from submarine sonar systems and oil rig operation manuals to military helicopters. He has built, restored, and cruised several yachts and lives aboard his own boat. He is a member of the ABYC and the Cruising Association. Learn more on his website.
Batteries
2.23 Lithium-ion Batteries. These batteries are rapidly entering mainstream service on boats. Lithium-ion-based battery technology is revolutionizing the mobile power market. They are a viable alternative to lead acid, AGM, and gel batteries. The batteries are available in a variety of voltages, including 12V, 24V, 36V, and 48VDC.
Lithium batteries quote peak current ratings. Typically, this is 68 degreesF (20 degreesC) for 5 to 10 seconds. There are many advantages, including almost no power loss when discharging to near 100%; the entire battery capacity is available. Lithium batteries possess a very high energy and power density. Other advantages include much lighter weights and having approximately 500% greater cycling capability than an AGM. Drawbacks are that these batteries are not generally suitable for engine starting and that there is a cost premium of about 100% to 300% or more. This is easily amortized by significantly longer life, much greater cycle life, and a power discharge and charge profile that is much friendlier to boating applications.
In late 2022 the UK company Aceleron launched the Essential 2.0 LFP battery, which is a Group 32 standalone LFP battery. This incorporates a battery management system (BMS) that has Bluetooth and controller area network (CAN bus) connectivity that allows network connection and remote monitoring of charge and discharge, cycle numbers, and internal cell temperatures. They have designed ergonomically correct carry handles, rubber feet to cushion against vibration, and cobalt-free lithium-iron phosphate technology. It has a peak power rating of more than 200A and is guaranteed for 5,000 cycles.
The American Boat and Yacht Council (ABYC) published revised lithium-ion battery recommendations in Standard E-13 in 2023. In 2022 the United States Coast Guard (USCG) requested that the ABYC test lithium-ion batteries and to try to replicate many of the reported issues and failures. They were unable to re-create any failures, regardless of how aggressive the testing was and have reportedly stated that lithium-ion batteries are safe. Following several major incidents, the jury is still out within the commercial maritime space.
a. Lithium-ion Battery Construction. Lithium-ion batteries use lithium cobalt dioxide (LiCoO2) or lithium manganese oxide (LiMn2O4) as a cathode. A lithium- iron battery uses lithium (Li), iron (Fe), phosphate (PO4), or LiFePO4, as the cathode. Like most battery technologies, the battery cell comprises two electrodes—the cathode and anode—with an insulative separator or barrier between them. The anode stores the lithium and is made from graphite carbon with a metallic backing. The cathode stores lithium and is manufactured with a metal oxide chemical compound (LiFePO4).
b. Lithium-ion Electrolyte. The electrolyte has a key role within the battery cell, transporting positive lithium ions between the cathode and anode. The electrolyte used within lithium battery technologies comprises a very high purity lithium salt, lithium hexafluorophosphate (LiPF6). This white crystalline powder is dissolved within an organic carbonate solvent, or nonaqueous solution. Several other chemical additives are used in the electrolyte to attain the required electrolyte properties.
c. Lithium-ion Battery Discharging. How much power can be delivered throughout the discharge cycle is the key to power supply quality and reliability. It should be noted that batteries can be damaged when overdischarged. This is usually a result of cumulative small residual or parasitic loads, such as devices that run all the time.
Table 2-9 illustrates typical voltage levels at various discharge levels of different battery technologies.
Table 2-9. Battery Discharge Comparisons
State of
Charge %
Lead Acid
Voltage
AGM/Gel
Voltage
Lithium-ion
Voltage Comments
100 12.7 12.80 14.40 Effective power in bold
90 12.6 12.64 13.40 Effective power in bold
80 12.42 12.50 13.30 Effective power in bold
70 12.34 12.37 13.25 Effective power in bold
60 12.15 12.27 13.20 End of effective capacity
50 11.96 12.01 13.10 End of effective capacity
40 11.81 11.81 13.10 Serious damage level
30 11.65 11.66 13.00 Serious damage level
20 11.39 11.12 12.90 Permanent damage level
10 10.94 10.50 12.00 Permanent damage level
2.24 Lithium-ion Battery Charging. The lithium ions pass through the separator and block the passage of the electrons. In the charging cycle, the ions pass from positive to negative; conversely, in the discharge cycle, they move from negative to positive. This movement of ions creates a potential difference and what we know as voltage. Lithium-ion batteries have a nominal voltage of 3.7vpc. Like other battery types, cells are connected in series to achieve the required battery bank voltage. That means four cells for a 14.8V battery. The cells are placed in parallel to increase the amp-hour capacity required. These batteries have a capacity rating of 1C, which means that a fully charged battery with a nominal capacity of 100A can discharge 100A in 1 hour, or 10Ah is 10A in 1 hour. Maximum discharge rates are usually rated at 2C. Like all batteries, regular charging and discharging is the best path to reliability. The average cell voltage across the discharge range is 3.6V to 3.7V; full charge is 4.2vpc, 3V when at minimum level. Running them down to 2.5vpc will damage them. A fully charged LiFePO4 battery will have a stable voltage of 13.3V to 13.4V; the lead-acid battery will be around 12.6V.
2.25 Lithium-ion Battery Installation. Do not install these batteries with other battery types, and do not be tempted to connect one in parallel with an AGM or other battery type, as there is an explosion and fire risk. Like all batteries, they do not tolerate rough mistreatment; absolutely do not short-circuit one. Do not overcharge them or subject them to reverse polarity. Do not crush or fracture the casing, and do not attempt to disassemble one—you may experience chemical burns as well fire and explosion. Lithium-ion battery age and life expectancy is subject to the temperature and the state-of-charge (SOC). The higher the temperature, the faster these batteries will age; ideally, the cooler they are kept, the better they will age.
2.26 Lithium-ion Battery Storage. These batteries are intolerant to temperatures exceeding 140 degreesF (60 degreesC) and should always be stored in a cool place. The nominal range is -4 degreesF to 140 degreesF (-20 degreesC to 60 degreesC); storage at temperatures below 68 degreesF (20 degreesC) will result in permanent capacity loss. If you are laying up your boat—as is common through many US and European winters in countries that experience subzero or temperatures well below 68 degreesF (20 degreesC)—it would be advisable to take the batteries out and store them somewhere at the house. There are SOC and voltage advisories as well. Short-term storage is recommended in the range of 3.0V to 4.2vpc in series. For long-term winter layups, this is at about 70% to 80% of battery capacity or less with a voltage level of 3.85V to 4.0V. The battery will lose storage capacity if it is maintained at 100%. They do not like being run down below the minimum voltage, which is between 2.4V and 3.0vpc.
2.27 Thermal Runaway. A frequent cautionary or advisory note is that lithium-ion batteries have a flammable electrolyte and are at risk of what is known as "thermal runaway." In certain situations, a lithium-ion battery can suffer very rapid internal heating, and once this exothermic reaction is initiated, it is hard to extinguish, contain, or stop. The initial cause of thermal runaway is an internal short circuit. Another potential cause is very fast charging and discharging, which generates heat. Thermal runaway can also be caused by damage to a lithium-ion battery due to careless and rough handling. Maintaining the battery bank within its nominal temperature range is important; therefore, effective ventilation is necessary. Avoid overcharging by only using charging systems, fast charge regulators, and battery chargers that are suitable for use with lithium-ion batteries; many are not. This is one of the reasons that a BMS should be installed at all times. The BMS monitors and shuts off when it detects either high or low voltage limits, high or low temperature limits, and when current charge limits are exceeded, both charging and discharging. The BMS should monitor these parameters at cell level. Only install batteries that are from manufacturers with integral cell-level BMS monitoring systems.
2.28 High Load Applications. Some equipment manufacturers specify only certain lithium-ion battery makes and models. Andersen is one of them for its compact deck winches. They only accept Super B, Mastervolt, and Victron Energy (MG Energy Systems) batteries. These batteries have undergone compatibility testing and have integral protection to prevent battery, motor, and systems damage. The use of these batteries in start battery applications has not been recommended. In late 2022, Mercury Marine approved the use of one battery type for starting outboard engines. That battery was the RELiON Model RB100-HP. This is a LiFePO4 battery with a minimum cranking amp rating of 800A for 8 seconds minimum at 20 degreesF (-7 degreesC). It has a peak acceptance charge of 165A for 1 minute, a maximum alternator charge rating of 150A, and a maximum charge voltage of 14.8V. Many engine makers advise that using a lithium-ion battery that is not approved will void the warranty.
2.29 Battery Management System (BMS). Many lithium-ion batteries incorporate an integrated BMS, and many are very comprehensive and sophisticated. The term "management" is the operative one, as these systems are also built-in protection devices. These systems are able to carry a 100A continuous load with a 200A surge capacity for up to 30 seconds. The systems also have high and low voltage protection along with short-circuit protection, as well as high and low temperature protection and automatic cell balancing. BMS modules may incorporate cell balancing circuits that balance series-connected sections during charging and discharge. Victron Energy has the Lynx Smart Battery Management System. The Lynx BMS is designed for lithium-ion batteries and incorporates state of charge monitoring, alarms, Bluetooth connectivity, and remote monitoring capability. Integrated battery management systems are now being offered by many manufacturers. BEP uses a system called Smart Battery Hub, which is an intelligent battery management system for multiengine installations.
Smart Battery Hub operates with remotely activated switches, automatic voltage sensitive switching, and emergency parallel functionality. The Lithionics NeverDie BMS includes battery state-of-health, status, fault codes, and SOC monitoring. The patent-pending BMS utilizes customized microprocessors and firmware that enable customization of the BMS to perform as a programmable logic controller (PLC). The NeverDie BMS is standard on all Lithionics Battery systems to guarantee that the lithium-ion batteries perform within rated
specifications. Optional Bluetooth monitors battery voltage, SOC, temperature, current, and status codes from a mobile device. The optional Bluetooth features include a live telemetry data feed and much more. A free app is available at the Google Play and Apple app stores.
The Navico Group has introduced the Fathom e-power system, an integrated lithium-ion power-management system that facilitates the operation of multiple onboard systems. The system package, which includes lithium-ion batteries along with sensors, switches, and controllers, is a product of Navico's vertical integration that includes companies within the group, such as Mastervolt, BEP, CZone, Ancor, and Blue Sea Systems. The system has an intuitive user interface that allows monitoring and control of power consumption using multifunction displays or an app for smart mobile devices. Check out lithionicsbattery.com, victronenergy.com, and navico.com/fathom.
2.30 Carbon Foam Batteries. Carbon foam batteries, another relative newcomer in the battery technology revolution, are a viable alternative to lithium-ion batteries in some applications. They offer several advantages, including far greater energy density, increased cycle life, and more efficient charging. Manufacturers include Ocean Planet Energy (Firefly Battery Company), a leading innovator in this space (fireflyenergy.com).
a. Carbon Foam Construction. Carbon foam batteries are constructed using a composite grid made of carbon-based porous foam. This foam consists of hundreds of thousands of highly porous spherical microcells. The structure allows enhanced efficiency of the lead acid reaction, as each microcell increases the active material area given the increased surface area and has 70% or greater porosity. This results in very high levels of thermal and electrical conductivity due to the high surface area-to-volume ratio. The cell anode is made of antimonide—copper blended with antimony—and this is electroplated onto the carbon foam. The carbon foam has a significant amount of air, but each bubble has a very large surface area. These discrete 3-D microcells form an electrolyte structure not unlike a beehive's honeycomb lattice. The cathode is made of nickel oxyhydroxide (NiO (OH)).
b. Carbon Foam Chemistry. Carbon foam batteries utilize a rather unique working principle. They are in fact half battery and half capacitor. A capacitor is able to store a charge and, similar to a battery cell, has two metal plates separated by a dielectric. The chemical reaction creates energy and stores this energy in the capacitor section of the cell in the form of electrolyte ions, which are attracted to the carbon anode. The negative plate is resistant to sulfation, which improves longevity; the drawback is that batteries will not charge to full capacity.
c. Carbon Foam Discharging and Charging. Charging efficiency is increased, and this is quoted as around 50%. One leading manufacturer recommends a complete 100% charge weekly as well as a periodic restoration charge. These batteries have a low discharge rate, which is an advantage. Carbon foam batteries are able to withstand occasional fast charging; however, they will degrade when charged at high current levels. The carbon foam battery is able to use conventional battery charging sources.
d. Cycling Ability. There are claims that these battery types have a much longer lifespan than a standard flooded-cell lead-acid battery. The most common factor quoted is 200% to 400%, although this is hard to substantiate. Another claim is that they can be discharged to 80% and 100% of capacity without sulfation or capacity reductions. In my opinion, I don't think any battery should be discharged to that depth; deep discharges of any battery result in reduced life.