12V 50Ah Battery: How to Specify a 12V 50Ah Cell for AGVs, Golf Carts and Small Solar Systems (2026)

Answer First

A 12V 50Ah battery is a sealed valve-regulated lead-acid (VRLA) cell that delivers 50 amp-hours at the C3 discharge rate from a 12V block, and it is the default building block for 48V mobility packs in resorts, golf clubs, warehouse AGV fleets and small off-grid solar systems. The specification that matters is not the label on the carton but the published figure set: 50 Ah at C3, a 230 × 140 × 180 mm case, 15.25 ± 0.2 kg, float at 13.5 V and equalisation at 14.1 V across the six cells of the block. Those five numbers decide whether the cell fits your bay, your charger and your budget. This guide sets out the published specifications of the 6-EVF-50 against its three closest siblings, shows how a 48V pack is built from them with the arithmetic written out, and gives the seven checks a buyer should run before issuing a purchase order to a supplier in Hangzhou, Rotterdam, Jebel Ali, Lagos or Chennai.

Key Takeaways

• A 12V 50Ah battery is rated 50 Ah at the C3 rate (three-hour discharge) and 13.5 V float across six cells, not at the cell level — the block is the sellable unit.
• The 6-EVF-50 publishes 230 × 140 × 180 mm and 15.25 ± 0.2 kg, which is what determines whether it physically fits a battery tray designed around the 6-DMF-45.
• A 48V pack of four 12V 50Ah cells gives 48 V × 50 Ah = 2,400 Wh and weighs 4 × 15.25 kg = 61.0 kg — the weight, not the energy, is usually the constraint.
• The closest sibling, the 6-DMF-52, gives 48 V × 52 Ah = 2,496 Wh at 4 × 13.7 kg = 54.8 kg, which is 6.2 kg lighter for 96 Wh more energy per pack.
• Float 13.5 V and equalisation 14.1 V are the correct setpoints for these VRLA cells; a charger set to 14.4 V will shorten service life without adding usable capacity.
• Cycle life is published at 350–600 cycles to 50–80% depth of discharge, and design life is 2–5 years — a different figure from the 20-year float life quoted for 2V tubular cells.
• The published charge current of 10.0 A means a 48V pack of four cells needs a 40 A charger, and a 50 Ah cell accepting that current replenishes in roughly 5 hours.

§1 — 12V 50Ah Battery Specifications

The table below reproduces the published specification for the 6-EVF-50 and its three nearest neighbours in the 12V VRLA range. Every value is taken from the manufacturer model page; the pack figures are derived and shown with their formulas.

One practical note on ordering: several of these model pages also list alternative weight variants in a horizontal comparison table — the 6-DMF-45 is additionally published at 13.1 kg and the 6-DMF-52 at 14.5 kg. Those reflect different case or terminal builds. Whichever variant you specify, have it confirmed on the order acknowledgement before the container is sealed, because a 1 kg difference per cell becomes 4 kg per four-cell pack.

§2 — The Pain

Three failures account for almost every 12V 50Ah battery complaint that reaches a distributor’s help desk in Hamburg, Durban or Mombasa.

The first is the label. A carton marked “50 Ah” tells you nothing about the case, the terminals, the cycle rating or the charge setpoints. Two cells from two factories can both print “12V 50Ah” and differ by 8 kg, by two years of design life and by 150 cycles. A buyer who quotes capacity alone will receive a cell that does not fit the tray and does not match the charger.

The second is the charger. A 12V VRLA block contains six cells in series, so the published float voltage of 13.5 V is 2.25 V per cell and the published equalisation voltage of 14.1 V is 2.35 V per cell. A common failure in the field is a charger left on its lead-acid default of 14.4 V, or a controller that never enters equalisation at all. Over-charge shortens life; under-charge causes sulphation and capacity loss within the first year. Neither shows up on the invoice.

The third is weight and tray geometry. A 48V pack of four 6-EVF-50 cells weighs 61.0 kg. Golf carts and AGV chassis have weight limits and, more often, have a battery tray designed for a specific case footprint. Swapping a 6-EVF-50 for a 6-DMF-52 without re-measuring the tray is how a 6.2 kg per-pack saving turns into a returns problem.

There is also a sourcing problem underneath all three. Buyers in Lagos, Chennai, Cairo and Jakarta often receive a quotation that lists “12V 50Ah AGM” with no datasheet reference at all, which makes the order impossible to compare across suppliers and impossible to re-order.

§3 — The Choice

Choosing between the four cells above is not a matter of taste. It is a trade between three published quantities: the case footprint, the cell weight, and the Ah per kilogram that follows from them. The pack table below shows the four possible 48V builds.

Read the table as a set of four answers to four different questions.

If your chassis has weight headroom and you want the largest footprint with a published weight tolerance, the 6-EVF-50 is the sensible default. It is also the only one of the four whose 230 × 140 × 180 mm footprint is matched by a published 6-EVF-50 model page with a full weight tolerance, which matters when you are holding a supplier to a tolerance.

If weight is the binding constraint, the 6-DMF-52 wins on both published weight and specific energy: 54.8 kg for the pack against 61.0 kg, and 45.5 Wh/kg against 39.3 Wh/kg. The 6.2 kg saved per pack is 24.8 kg across a ten-vehicle fleet. The 6-DMF-52 model page carries the full specification for that cell.

If you need the lightest pack of all and can live with less energy, the 6-DMF-45 gives 49.2 kg and 2,160 Wh, which suits smaller AGV platforms and towable carts where gross vehicle weight is capped.

If the duty cycle demands more runtime per charge rather than less weight, the 6-EVF-60 gives 2,880 Wh per pack and needs a 48.0 A charger, so the charger is the constraint rather than the battery.

The wider 12V VRLA range, including the 6-DZF and 6-DMF series that cover everything from 12 Ah to 58 Ah, is set out on the CHISEN 12V VRLA product index.

§4 — The Framework

Seven checks turn a vague enquiry into an order a factory can fill correctly.

1. Demand the published figure set, not the label. Ask for capacity with its rate basis (C3), dimensions in millimetres, weight with tolerance, terminal type, float voltage, equalisation voltage, maximum charge current, cycle life and cut-off voltage. A supplier that answers all ten cannot be guessing.

2. Fix the charge setpoints in writing. 13.5 V float and 14.1 V equalisation for the block; 2.25 V per cell and 2.35 V per cell once you do the arithmetic. Confirm that your charger controller can be configured to both, and confirm the equalisation period. If the answer is “it is automatic”, ask which controller models are tested.

3. Match the charger to the published charge current. The 6-EVF-50 accepts 10.0 A, so a four-cell 48V pack needs a 40 A charger. A 30 A charger extends the recharge window: 50 Ah ÷ 10.0 A = 5 hours is the theoretical minimum at the published current, and a 30 A charger stretches that to 50 Ah ÷ 7.5 A = 6.7 hours before losses.

4. Check the depth-of-discharge window you are buying. The published 350–600 cycle figure holds at 50–80% depth of discharge. If your duty cycle runs to 100% depth, the cycle rating in the table does not apply to you, and you should size up rather than accept the headline figure.

5. Verify the temperature envelope. The published working range is −15 °C to 50 °C, and capacity is quoted at 25 °C. Self-discharge is ≤3 % per month at 25 °C. A fleet parked outdoors through a Hamburg winter or a Santos summer does not see 25 °C for most of its life; ask the supplier what capacity remains at the extremes.

6. Fix the variant on the acknowledgement. Because the model pages carry alternate weight variants, the order line must state the case, the terminal and the weight tolerance — not just the model code. Add the requirement that the batch matches the datasheet revision on the packing list.

7. Agree the acceptance test. For container shipments to Santos, Jebel Ali, Lagos or Port Said, specify what happens on arrival: a sample capacity check at the C3 rate, a float voltage check across the block, and the rule that a failing sample is settled by re-inspection at an agreed laboratory rather than by argument.

§5 — The Trust

The 6-EVF-50 and its siblings are built on a VRLA line inside a manufacturer operating 8 production bases with an annual capacity of 70 million kVAh, under a certified quality management system with ISO 9001 and ISO 14001 certification, with CE, UL and IEC conformity for the markets each cell ships into. The full 12V VRLA battery index is maintained on the manufacturer site, and every figure in this article comes from the individual model page rather than from a catalogue summary.

Two things deserve emphasis for a buyer who is being asked to pay for assurance.

First, a certification covers a system, a scope and a date — not a particular carton. ISO 9001 certifies that the quality management system is documented and that corrective action happens; it does not certify that one cell holds 50 Ah. That is what the published capacity, the type test and the acceptance test are for. Ask for the certificate number, the scope statement, the registered address and the validity dates, and then check the cell on its own merits.

Second, the difference between a published specification and a marketing line is the whole value of this exercise. A supplier who quotes “12V 50Ah AGM, top grade” is telling you nothing. A supplier who quotes “6-EVF-50, 50 Ah at C3, 230 × 140 × 180 mm, 15.25 ± 0.2 kg, float 13.5 V, equalisation 14.1 V, 10.0 A maximum charge current” is telling you everything you need to engineer the pack, write the charger setting and defend the claim at the goods-in dock.

For importers who buy through a distributor rather than direct, ask the distributor for the manufacturer’s model page URL and the batch reference. Both can be checked before the container is opened, and both remove the single largest source of dispute in this category.

§6 — FAQ

Q1. What does 50 Ah actually mean on a 12V 50Ah battery? It means 50 amp-hours delivered at the C3 discharge rate — the three-hour rate — down to the cut-off voltage of 1.75 V per cell, at 25 °C. It does not mean 50 Ah for the whole day. On a longer, five-hour discharge the usable figure is lower, and on a two-hour discharge it is higher. Any quotation that gives capacity without the rate basis is incomplete.

Q2. Can I substitute a 6-DMF-52 for the 6-EVF-50 in an existing 48V pack? Usually yes, and it is often an improvement on weight: the 6-DMF-52 gives 48 V × 52 Ah = 2,496 Wh at 4 × 13.7 kg = 54.8 kg, against 48 V × 50 Ah = 2,400 Wh at 4 × 15.25 kg = 61.0 kg. Before you do, confirm the case footprint fits the tray — 224 × 135 × 175 mm against 230 × 140 × 180 mm — and confirm the charger can deliver 4 × 10.4 A = 41.6 A. The terminal dimension stays at φ11.8-M6, but it is a different moulding, so check the lead length and the retaining hardware.

Q3. What charger do I need for a 48V pack of four 12V 50Ah batteries? A 48V charger with a 40 A output, because the published maximum charge current is 10.0 A per cell and 4 × 10.0 A = 40 A. Set the float at 13.5 V and the equalisation at 14.1 V for the 48V string, which is 2.25 V and 2.35 V per cell respectively. Give the charger a temperature-compensation input if the pack sits in a hot climate, because a 25 °C setpoint in a 45 °C bay is an over-charge condition.

Q4. How long will a 12V 50Ah battery last in a solar application? In float standby with solar charging the published design life is 2–5 years and the published cycle life is 350–600 cycles at 50–80% depth of discharge. In a solar duty cycle the binding factor is usually the number of cycles the site sees, not the calendar. If the site is in Jebel Ali or Chennai, expect the temperature side of the envelope to matter as much as the cycle count; if it is in Valencia or Durban, confirm the cabinet ventilation, because the working range stops at 50 °C.

Q5. Is 13.5 V the correct float voltage, or should it be 13.6–13.8 V? For a VRLA block, 13.5 V is the published float voltage for these cells, which is 2.25 V per cell across the six cells of the block. A setting of 13.8 V is 2.30 V per cell and pushes the cell above its intended float point. Over a year that difference shows up as shortened service life and more frequent water loss, and it does not add usable capacity. Ask the supplier to confirm the setpoint against the model page rather than against a generic lead-acid chart.

Q6. What is the difference between a 6-EVF-50 and a 6-DMF-50? Both are 12V VRLA cells in the same capacity class, and the EVF and DMF series differ in plate construction and case format rather than in chemistry. The 6-EVF-50 is published at 230 × 140 × 180 mm and 15.25 kg; the closest DMF equivalent in this range is the 6-DMF-52 at 224 × 135 × 175 mm and 13.7 kg. If you are qualifying a new supplier, compare the published dimensions and weights side by side rather than relying on the series name, because the case geometry is what determines whether the cell physically fits your application.

Q7. Can a 12V 50Ah battery be used for an AGV in an e-commerce warehouse? Yes — the manufacturer lists automated guided vehicles in e-commerce warehousing and smart factory environments among the applications for the 6-EVF series, alongside 4–8 seat electric sightseeing vehicles at resorts and theme parks, golf carts, 1–3 tonne electric forklifts and floor-scrubber platforms. The specification to check is the cycle rating: a warehouse AGV that runs two shifts with deep recoveries will consume cycles faster than a standby application, so confirm the 350–600 cycle figure at your actual depth of discharge.

Q8. What should be on the purchase order for a 12V 50Ah battery? The model code and the case and weight variant, the float and equalisation voltages, the maximum charge current, the cycle rating and depth of discharge, the terminal type, the batch reference, the test certificate and the acceptance procedure on arrival. Include the requirement that the shipped batch matches the published model page revision. If the order will be shipped to a port such as Rotterdam, Santos or Mombasa, state the agreed laboratory for a failing-sample inspection.

Expert Summary

A 12V 50Ah battery is a well-understood component, and the specification is public: 50 Ah at C3, 230 × 140 × 180 mm, 15.25 ± 0.2 kg, 13.5 V float, 14.1 V equalisation, 10.0 A maximum charge current, 350–600 cycles at 50–80% depth of discharge, 2–5 years design life. The 6-EVF-50 is the reference cell, and the 6-DMF-52 is the sensible alternative when weight matters more than footprint, delivering 45.5 Wh/kg at the pack level against 39.3 Wh/kg.

The commercial value of specifying precisely is larger than the price difference between the cells. A quotation built on a published figure set can be compared across three suppliers in ten minutes and defended at the goods-in dock. A quotation built on a label cannot be compared at all, and the difference shows up three months later as a warranty claim.

Two figures deserve a final emphasis for buyers working outside Europe. First, the 40 A charger requirement for a 48V pack of four cells is set by the published maximum charge current, not by marketing; if your charger is sized below it, the recharge window stretches and the pack spends more of its life in a partially discharged state. Second, the published cycle rating assumes 50–80% depth of discharge, so if your AGV or cart runs deeper than that, ask for the rating at your actual depth before you commit to a volume.

For importers into markets served from Rotterdam, Jebel Ali, Santos, Lagos or Chennai, the sequence that works is simple: fix the published specification first, then let suppliers compete on it. The one-page figure set in §1 is enough to run that process.

Contact CHISEN

Send the target application, the required capacity, the case dimensions you need to fit and the quantity to the CHISEN export desk, and you will receive a quotation against the published specification, the datasheet and the current lead time.

• Email: jack@chisen.cn or sales@chisen.cn
• WhatsApp: +86 131 6622 6999
• 12V VRLA product index: https://www.chisen.cn/en/LeadacidBattery/EVF.html
• 6-EVF-50 model page: https://www.chisen.cn/en/6-EVF-50/12V50Ah.html
• 6-DMF-52 model page: https://www.chisen.cn/en/6-DMF-52/12V52Ah.html

Related reading on the CHISEN knowledge centre: 12V VRLA selection guidance, deep-cycle charge setpoints, and pack-sizing method for AGV and traction applications.

CHISEN Battery — lead-acid cells and systems for telecom, solar, UPS, AGV and traction applications. 8 production bases, 70 million kVAh annual capacity, ISO 9001 and ISO 14001 certified.

CHISEN Battery Team

Engineering and export team at CHISEN Battery, Hangzhou, China. Lead-acid and lithium battery manufacturer, ISO 9001 / CE / UL certified, exporting to 50+ countries.

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