Drake Marine has supplied marine batteries in Thailand since 2002. This page is what we tell customers who walk into the counter in Trang: how to size a bank, what actually survives a tropical year, and how to make a set last.
What we hold in stock
Fullriver sealed AGM, from 55Ah to 260Ah in 12V, in both deep cycle and engine start. It is on our shelves in Trang, not on a container somewhere — which is the difference between sailing this week and waiting a month.
- Deep cycle marine batteries — house banks, 55–260Ah
- Engine start marine batteries — high cranking current for marine diesel and petrol
- Marine battery chargers — multi-stage, with temperature compensation
- 2V stationary and solar batteries — Fullriver HGXL single cells, 50–3000Ah, for shore installations, solar, telecom and UPS banks
Sizing a house bank
A house bank is sized on what you actually draw overnight, not on what fits the locker. Add up the amp-hours your fridge, lights, autopilot, instruments and pumps consume between charges, then size so that overnight draw sits comfortably inside the usable capacity.
Our marine battery bank and cable size calculator does the arithmetic, including the cable gauge — undersized cable is one of the most common faults we see on boats brought to us, and it quietly wastes charging current every single day.
Why Fullriver AGM, specifically
80% usable depth of discharge. Fullriver’s own manual sets the working limit at 80% DoD, where a great deal of quality AGM is held to 50%. In practical terms that is capacity you have already paid for and can actually use. Habitual deep cycling shortens service life on any battery, so size the bank properly and you get the benefit without the cost.
Sealed VRLA construction. Non-spillable, no free acid, nothing to top up, and safe to mount in enclosed spaces where a flooded battery would not be acceptable.
It flies. Sealed AGM and GEL are classified non-hazardous for transport under 49 CFR 173.159(d) and IATA A67/A48. A replacement or an upgrade can travel by air to wherever the boat actually is — days, not weeks, anywhere in the world. If you are mid-passage in a remote anchorage, this is the single most useful property a battery can have.
Bench-tested before dispatch. Every battery is tested in Trang by the same team that fits this equipment to boats.
Making a set last in the tropics
Always charge with temperature compensation. In tropical heat that one setting protects your investment more than anything else you can fit. Every charger we supply supports it.
Recharge fully after every use. A bank left sitting part-charged is a bank working against itself. A proper multi-stage charger finishes the job; a cheap one stops early and leaves capacity on the table.
Keep the connections clean and the cable right. Voltage lost in undersized or corroded cable never reaches the battery, and the symptom looks exactly like a tired bank.
AGM or lithium?
Lithium is lighter and accepts charge faster, and it suits boats with heavy daily cycling and the budget to match. AGM remains the sensible choice for most cruising and working boats in Thailand: lower cost per usable amp-hour up front, no BMS to fail, no dangerous-goods paperwork for shipping, and genuinely available here rather than on order. We supply both — tell us how the boat is used and we will tell you honestly which one earns its money.
Delivery across Thailand and worldwide
Free delivery to Trang, Krabi and Phuket on our own weekly courier run, whatever the size. Free nationwide over $250. International orders ship worldwide with freight quoted at cost and invoiced separately before dispatch — we never mark shipping up.
Talk to someone who fits these for a living
If you are not sure what your boat needs, email hello@drakemarine.com with the boat, how you use it and what is currently fitted. You will get an answer from the people on the counter in Trang, not a call centre.