Fullriver DC85-12 — Deep Cycle AGM Battery, 12V 85Ah
True deep-cycle AGM for house banks on boats, second batteries in 4x4s and campers, off-grid homes and solar systems. Thicker plates and more lead than standard AGM for maximum reserve capacity and cycle life. 12V · 85Ah (C20) · 25.1 kg · maintenance-free.
- Genuine Fullriver, in stock at our Trang warehouse
- Bench-tested before dispatch
- Manufacturer’s warranty — we handle claims for you here in Thailand
- 30-day returns on unused items — how returns work
Delivery & shipping
- Free local delivery — Trang · Krabi · Phuket
- Thailand-wide courier, typically 1–3 days
- Worldwide shipping by courier & sea freight
- Non-spillable sealed battery — classified non-hazardous (49 CFR 173.159(d), IATA A67/A48), air-transportable worldwide with no dangerous-goods surcharge.
Fair price check
Our price is the manufacturer's home-market RRP — what this gear sells for where it's made. Branded marine equipment in Thailand typically retails 15–90% above that, when prices are published at all. Ours doesn't.
About this product
The Fullriver DC series is a true deep-cycle AGM range: thicker plates and a higher lead content than conventional batteries deliver more reserve capacity and more cycles under repeated deep discharge. Sealed, valve-regulated and completely maintenance-free, the DC85-12 is our standard recommendation for house banks in the tropics, on boats and in off-grid homes alike — it tolerates heat, vibration and the daily charge/discharge cycle.
More of the capacity you paid for
Fullriver rate the DC series to an 80% depth of discharge — their own published limit — where much quality AGM is held to 50%. On this 85 Ah battery that is the difference between planning around 43 Ah and planning around 68 Ah, so a smaller, lighter bank can carry the same night away from the mains. Deep cycling is still work: a bank that is fully recharged after every use will outlast one that isn’t, so pair it with a multi-stage AGM charger set up with temperature compensation. In tropical heat that one setting protects your investment more than anything else you can fit.
Specifications — DC85-12
| Nominal voltage | 12V |
| Capacity @20hr | 85 Ah |
| Capacity @100hr | 95 Ah |
| Chemistry | AGM, sealed VRLA, non-spillable |
| Weight | 25.1 kg |
| Dimensions (L×W×H) | 260 × 169 × 236 mm |
| Terminals | M8 + brass auto post |
| BCI Group | 24 |
Charging
Charge with an AGM profile. Fullriver specify 14.7 V bulk/absorption and 13.7 V float at 25 °C, temperature-compensated at −4 mV/°C per cell, and a bulk current of about 20% of the 20-hour capacity — roughly 17 A for one DC85-12, or 34 A for a pair. Matching multi-stage chargers: Kisae Abso AC1220 20 A for one battery, Kisae Abso AC1240 40 A for a pair, and for a 24 V bank of four the Kisae Abso AC2450 50 A (24 V). Not sure what bank size or charger you need? Use our battery bank & cable size calculator or message us on LINE or WhatsApp.
Sealed and non-spillable — classified non-hazardous for transport (49 CFR 173.159(d), IATA A67/A48), so it ships by air, sea or road with no dangerous-goods surcharge and can be mounted in any orientation except inverted. Every battery is bench-tested in our Trang warehouse before dispatch.
Delivery in Thailand
Free delivery in Trang, Krabi and Phuket on our weekly courier run; nationwide courier typically 1–3 days. Collection from our Trang warehouse is welcome. Covered by Fullriver’s manufacturer’s warranty — we handle any claim for you here in Thailand; ask us for the current terms.
Downloads
Building a house bank with the DC85-12
Two DC85-12 in series give 24 V 85 Ah; two of those pairs in parallel give 24 V 170 Ah (4.1 kWh stored, about 3.3 kWh usable within Fullriver's 80% limit). Four in parallel give 12 V 340 Ah. Keep every cable in a parallel set the same length, fuse the bank at the battery, fit the temperature sensor to a middle battery, and replace a bank as a set rather than one battery at a time.
Charging a 24 V bank of four: bulk current of about 34 A, so the Kisae Abso AC2450 50 A 24 V charger from a generator or the mains, or a 24 V solar controller sized to your panels. Size the bank and the cable, or send us what you run on LINE and an engineer will check it.
As a second battery in a 4x4, pickup or camper
Fitted in the canopy or under a seat, the DC85-12 gives 68 Ah of usable energy at Fullriver's 80% depth of discharge: enough for a 35–45 L compressor fridge, LED lights and phone charging for a night without starting the engine. It is sealed, so it can be mounted on its side, and it shrugs off corrugations.
Charge it from the vehicle with a DC-DC charger rather than a split-charge relay, so a smart alternator and a long cable run still deliver a full AGM charge: for this battery the KISAE Abso DMT1230 (30 A). Every KISAE charger comes with a free temperature sensor and its page carries the manufacturer's cable and fuse table. Add a battery monitor and you can see the state of charge instead of guessing.
On a longer trip the battery is topped up as you go: an hour's driving on a 30 A DC-DC charger returns about 27 Ah, and 200 W of solar on the roof about 50 Ah a day in Thai sun, so a fridge, lights and phones (about 40–50 Ah a day) keep going for a week or more.
Read dual-battery systems explained, or use the Drake SVO sizing calculator and send the result to an engineer on LINE to check, free.
Questions
Do I need a DC-DC charger, or will a relay do?
Many modern vehicles have smart alternators that lower the voltage once the starting battery is full, so a relay leaves an AGM battery part-charged. A DC-DC charger gives it the full AGM profile Fullriver specify (14.7 V absorption, 13.7 V float); the dual-battery guide explains why.
Can it be mounted on its side?
Yes. It is sealed and non-spillable, so it can be mounted upright or on its side, which gives you more options in a canopy, under a seat or in a locker.
How do I look after it in the heat?
Mount it shaded with some airflow, and charge it with temperature compensation: Fullriver specify −4 mV/°C per cell, and the battery temperature sensor that does this comes free with every compatible KISAE charger.
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