The full sales program: usable energy and weight, the safe-lithium story, a lithium-only system on Epoch · Egis XD · Victron · Wakespeed, bank strategy and simplification, the start capacitor, and an install to ABYC E-13-2025. Twelve chapters, each a lesson with the pitch and a check.
Before you start
A full sales program for the lithium conversion: the customer pitch, the safety story, the system (Epoch · Egis XD · Victron · Wakespeed), bank strategy, the install standard, and the estimate. Each chapter is a lesson with the actual pitch line and a check; an in-depth final exam unlocks your certificate. Brand specifics marked "⚑ Verify" must be confirmed against the manufacturer before quoting as fact.
Double the real capacity, far smaller, far lighter.
LiFePO4 — not the chemistry that makes the news.
Epoch · Egis XD · Victron · Wakespeed, to ABYC E-13-2025.
Chapter 1
The customer asks why they'd spend more than a basic lead-acid swap.
Lead-acid is old technology — especially as a house or start bank. LiFePO4 wins on the things a boater actually feels every weekend. We don't sell chemistry; we sell usable energy, weight, space, and years of not thinking about it.
With lead-acid you only get to use about 50% of the rated capacity before you start shortening its life. With LiFePO4 you use roughly 80–100%. So a 100 Ah lithium bank does the work of a ~200 Ah lead bank — same real energy, far less battery.
A 100 Ah LiFePO4 weighs about a third of an equivalent AGM (~26 lb vs ~65 lb), and because you need far fewer amp-hours of rated capacity, the physical battery box ends up far smaller — not just half. On a boat, that weight and space back is real.
This is one of the biggest real-world wins. Lead-acid forces a slow finish: as it nears full it can only accept a trickle, so the last 20–30% drags out through hours of absorption. LiFePO4 has very low internal resistance and accepts a high charge current almost all the way to full — no long taper. With a properly sized charger or alternator it refills in a fraction of the time, which means far less generator and engine run-time just to top the bank up.
Source: RELiON / industry comparisons.
Chapter 2
"Isn't lithium the stuff that catches fire?"
The fires people see in the news are almost always NMC and other high-energy lithium chemistries — phones, e-bikes, EVs. We use LiFePO4 (lithium iron phosphate), which is a fundamentally more stable chemistry. Knowing the difference turns a fear into a selling point.
In LiFePO4, the oxygen is locked into a very strong iron-phosphate structure. Even fully charged, that cage stays put and doesn't release oxygen — and oxygen is what feeds a battery fire. NMC uses a layered oxide that can release oxygen when it overheats, which is what makes it burn.
Sources: LFP vs NMC safety · pv-magazine.
Chapter 3
The customer wants to 'keep the old start battery too.'
This is a hard rule, not a preference: we never keep a lead-acid battery aboard. Leaving lead in the boat alongside lithium is the single most common way to destroy a battery and start a boat fire. We build the entire system as one lithium system — and we can still guarantee the boat cranks every time.
The old reason to keep a lead start battery — cranking — is solved without it. Epoch's dual-purpose batteries carry the CCA to crank the engine directly, and on larger engines we add a Kold Ban KBI capacitor (Chapter 9) for a guaranteed, surge-proof start. So there is simply no reason to keep lead aboard — and every reason not to.
Chapter 4
Every boat's electrical layout is a little different.
Don't assume any one layout. A boat may or may not have a thruster bank, and many boats carry several banks — house, start, thruster, windlass, genset, even a dedicated electronics bank. Start by finding out what's actually there.
One of lithium's quiet advantages: with the right batteries and smart switching, we can often simplify the bank layout — fewer, better-managed banks instead of a tangle of half-dead lead batteries doing different jobs. Less weight, less maintenance, less to go wrong.
Chapter 5
The customer asks 'which battery do you use, and why that one?'
We install Epoch — a battery engineered for marine use, not a generic drop-in. It's ABYC, NMEA and NMMA certified, and it brings the cranking power, cold-weather charging, and phone-based monitoring a real marine system needs. Know it cold — it's the centerpiece of the proposal.
Epoch's Pro Series dual-purpose batteries deliver real cold-cranking amps — the 12V 120Ah is rated 1100 CCA (800 A for 10 seconds), enough to start outboards up to ~250 hp — while still serving as deep-cycle house power. This is exactly why we never keep a lead start battery: the Epoch cranks the engine itself.
This is one of the most tangible selling points in the whole pitch — hand the customer their phone and let them watch their own battery. The Epoch app connects over Bluetooth and shows, in real time:
No lead-acid battery can tell you any of that. Showing a customer their own cell voltages and amp-hours used on a phone makes the technology real — and makes the price make sense.
LiFePO4 must not be charged below freezing. Epoch's self-heating models warm the cells automatically so the bank can accept a charge in the cold — important in the Pacific Northwest — without the owner ever thinking about it.
Epoch backs each LiFePO4 battery with an 11-year limited warranty against defects in materials and workmanship — a major part of the value story versus a cheap lead swap.
Sources: Epoch 11-Year Warranty · Epoch Pro Series (CCA) · Epoch BMS.
Chapter 6
How the power is switched, protected, and controlled.
We pair the batteries with Egis power management — increasingly the XD series, which puts battery switching and charge management right on the boat's electronics network.
The XD series are high-amp remote battery switches and charge-management relays that are controllable over NMEA 2000 — the first to build N2K directly into a battery switch. They can be operated by knobs at the unit or from the network, and they report switch status, manual-override engagement, and the voltage of every connected battery back to the system.
Because it's on NMEA 2000, the customer can switch and monitor their batteries right from their chartplotter / MFD — the same screen they already use for navigation. And because it rides the existing N2K backbone, it replaces a bundle of heavy analog control wires, which means a cleaner install and lower cost.
Source: Panbo — Egis XD · Egis Mobile Electric.
Chapter 7
Tying the system together and proving it'll be supported for years.
We build the control and monitoring layer on Victron — a mature, deeply supported ecosystem. That long-term support matters: a lithium system is a 10-year investment, and Victron keeps its products updated and serviceable for the long haul.
Source: Victron — Cerbo GX.
Chapter 8
Will the engine charge the new bank safely?
Lithium changes how the engine charges. A standard internally-regulated alternator isn't safe on a lithium bank — if the BMS disconnects mid-charge, the alternator can spike and damage itself and the electronics.
We fit an externally regulated alternator setup. Default is the Wakespeed WS500; the Balmar MC-618 is the alternate (you'll choose in the estimator). The external regulator controls charge current and watches alternator temperature so it charges hard but safely.
Check whether the boat's alternator is already externally regulated. Either way, record the engine data — make, model, and alternator output — so the charging system is sized correctly.
Chapter 9
Making sure a lithium boat always cranks.
Lithium banks can deliver big current, but the BMS protects itself by limiting a sudden surge — and a big engine's starter pulls exactly that kind of surge. On larger engines we bid a Kold Ban KBI capacitor so the boat always cranks.
It's a supercapacitor that stores a burst of energy and delivers a strong, clean shot to the starter — like a fresh battery, every time — then recharges itself from the house bank in about 30 seconds. Crucially for lithium, it absorbs the big inrush of cranking so the BMS doesn't trip and shut down at the worst moment.
We bid the KBI on engines over 150 hp, and we always confirm the engine's CCA (cold-cranking amps) requirement so the start side is sized right.
Source: Kold-Ban / KBi.
Chapter 10
Customers who anchor out want power without the engine.
Lithium pairs beautifully with solar — it accepts charge efficiently and holds it without the losses lead-acid suffers. For anyone who anchors out, solar is an easy, popular add to the proposal.
A well-built lithium system takes charge from several places: shore power (through the MultiPlus II), the engine (through the externally regulated alternator), and solar (through an MPPT controller). Victron ties them together so they cooperate.
Chapter 11
Why our install is safe, to code, and worth it.
Everything goes in to the marine standards. That's not box-ticking — it's the difference between a system an insurer and surveyor respect and a science project.
LiFePO4 terminals are generally M8. We run two cables per battery rather than stacking four — it keeps the connection clean and avoids unnecessary draw and imbalance between cells. (The technician course covers the full fusing and wire-run detail.)
Source: ABYC E-13-2025 (Panbo).
Chapter 12
Turning the conversation into a clean, visual proposal.
Use the LiFePO4 Sales Estimator. Pick the boat (it auto-populates known specs for common models), capture the engine and CCA, the banks the boat actually has, solar, and the alternator regulator — and it graphs the usable-energy gain (their current bank vs the proposed lithium bank). Then send it to the customer.
Final certification
A short check ran at the end of each chapter. Pass this final at 80% to unlock your certificate.