Forklift Battery 48V: AGM Pack Sizing for Electric Forklifts (2026)

Answer First

A forklift battery 48V pack is four 12V traction batteries connected in series, and every commercial decision about it follows from that single fact: energy, weight, charger size and charge time are all set by which 6-EVF unit you repeat four times. The CHISEN 6-EVF line publishes six capacities for that build — 60 Ah, 80 Ah, 100 Ah, 120 Ah, 135 Ah and 150 Ah at the 3-hour rate to a 1.75 V/cell cut-off — and each publishes its own dimensions, weight and maximum charge current. A 48V pack built from four 6-EVF-150 units delivers 48 V × 150 Ah = 7,200 Wh and weighs 4 × 48.5 kg = 194.0 kg; the same 48V pack built from four 6-EVF-60 units delivers 2,880 Wh and weighs 4 × 18.8 kg = 75.2 kg. Float across the string is 4 × 13.5 V = 54.0 V and equalisation is 4 × 14.1 V = 56.4 V. This guide sizes those packs from published data only, so the truck class, the shift pattern and the charger can be fixed before a quotation is requested.

Key Takeaways

• A 48V forklift pack is 4 × 12V in series: 48 V × Ah equals the pack energy, so four 6-EVF-150 units give 48 V × 150 Ah = 7,200 Wh.
• Published weights make the pack heavy: 4 × 18.8 kg = 75.2 kg for the 60 Ah build, rising to 4 × 48.5 kg = 194.0 kg for the 150 Ah build — a 118.8 kg difference that changes the counterweight balance and the floor loading.
• The 6-EVF range is rated at the 3-hour rate to a 1.75 V/cell cut-off, so 60 Ah means 60 Ah at C3, not at C10.
• Every published maximum charge current is 0.2 C: 12.0 A for the 6-EVF-60, 20.0 A for the 6-EVF-100, 24.0 A for the 6-EVF-120, 27.0 A for the 6-EVF-135 and 30.0 A for the 6-EVF-150. In a series pack the string charges at the cell rating, so the 48V charger is a 48V/30 A unit, not 120 A.
• Float is 13.5 V and equalisation 14.1 V for a 12V unit, which is 54.0 V and 56.4 V across a 48V pack and 2.25 V per cell in float.
• Published cycle life is 350-600 cycles at 50-80% depth of discharge, and float design life is 2-5 years — these are separate numbers and a buyer quoting only the cycle figure is quoting the wrong one for a standby duty.
• Working range is −15 °C to 50 °C and storage −20 °C to 45 °C, which puts a container-side warehouse in Rotterdam or Durban inside the published window but a dock in Chennai in summer close to the upper limit.

§1 — Forklift Battery 48V Specifications

All values below are read from the manufacturer model pages for each 6-EVF unit, or derived from them by arithmetic. The 6-EVF range is the AGM valve-regulated traction series: high-strength AGM grids, cadmium-free and mercury-free plates, and the published compliance set is GB/T 32620.1-2016 and GB/T 32620.2-2016 for electric road vehicle lead-acid batteries, with JB/T 2599 referenced, alongside CE, RoHS, REACH, MSDS and IMDG sea freight documentation.

Two details in that table change how a 48V quote should be read.

The first is the capacity rate. The 6-EVF range publishes capacity at the 3-hour rate to a 1.75 V/cell cut-off, not at the 10-hour rate. That is correct practice for a traction duty, where the truck draws close to its rated current during a lift, but it means a “120 Ah” unit on this list is not directly comparable to a “120 Ah” VRLA quoted at C10 for standby duty. Ask for the rate and the cut-off on the order line, and compare like with like.

The second is the charge current. Every published value is exactly 0.2 C, which tells the buyer the charger’s amperage before any arithmetic: a 48V pack from four 6-EVF-150 units takes a 48V/30 A charger, and a 48V pack from four 6-EVF-100 units takes a 48V/20 A charger. Because the four units are in series, current passes through all of them, so the pack rating is the cell rating — the pack current is not the sum of the four.

§2 — The Pain

Three specification failures account for most of the unusable 48V forklift quotations a buyer receives.

The first is a 48V pack described only by voltage and amp-hours. “48V 150Ah forklift battery” describes an energy quantity and nothing about the physical pack. The four 6-EVF-150 units that hold 7,200 Wh occupy 4 × 483 mm of length in the truck bay, weigh 194.0 kg and split across two rows. The same energy in a different case format — six 8V 150 Ah units — weighs 6 × 34.8 kg = 208.8 kg and occupies 6 × 260 mm. A buyer who specifies only volts and amp-hours cannot control the bay envelope, the floor loading or the counterweight balance, and by the time the pallet arrives the frame will not take it.

The second is a charger sized on the sum of the battery ratings. Four units rated 30 A each do not accept 120 A. A 120 A charger on a 48V pack charges each unit at 120 A, which is 0.8 C on a 150 Ah cell — roughly four times the published maximum. The damage is not immediate; it is elevated temperature on charge, electrolyte loss in the AGM separators and a shortened service life across the whole pack. The correct charger is 48V at the published cell rating.

The third is cycle life quoted where float life is needed. The 6-EVF range publishes two different lifetimes, and they are not interchangeable. The float design life is 2-5 years. The cycle life is 350-600 cycles at 50-80% depth of discharge, and the same model pages also carry a 400-650 cycle figure in their detailed table, which is why the two numbers circulate in parallel in the market. A warehouse running one charge cycle a day is buying cycles; a fleet vehicle parked at the dock for four hours between shifts is buying float standby capability, and the reserve margin for that duty comes from the 2-5 year float design life and from sizing the pack against the load, not from the cycle figure.

There is a fourth, quieter problem. A forklift battery spends its life in a bay that is either open to the dock or in a charging alcove with poor ventilation, and the published working range of −15 °C to 50 °C is a wide band. A pack charged at 50 °C in a closed alcove in Chennai or Jebel Ali is outside the comfortable middle of that band, and the published guidance is explicit that charging should be carried out on a cooled battery and not in hot sun or an enclosed high-temperature space. That is a charger siting decision, and it belongs in the enquiry.

§3 — The Choice

The table below is the actual selection: the same 48V pack, built from the four published 6-EVF units. Every weight and energy figure is derived from the unit values in §1.

Read across the rows and the pattern is clear. The specific energy sits in a narrow band of 36.0 to 38.3 Wh/kg for every build, so a bigger pack is heavier in proportion to what it stores rather than being efficiently or inefficiently designed. The 4 × 6-EVF-60 build is the lightest per unit of energy at 38.3 Wh/kg; the 4 × 6-EVF-120 build carries the same 36.0 Wh/kg as the 135 Ah build, because the 120 Ah case is long at 407 mm and the 135 Ah case is tall at 280 mm with a smaller footprint of 338 × 172 mm. If the bay is short and narrow, the 6-EVF-135 may be the only unit that physically fits, and that constraint should override the energy comparison.

The 6-EVF-100 build at 126.0 kg and 4,800 Wh is the common middle choice for 1 to 3 tonne trucks working a single shift, and its 20 A charger is also the most widely deployed 48V charger size. The 6-EVF-150 build at 194.0 kg is a two-shift or high-utilisation pack, and it is the heaviest item that a 1 tonne counterbalance truck is designed to carry as battery — which is why the truck’s own lift and counterweight calculation has to be done with the published 194.0 kg figure and not with a generic “150 Ah battery” weight.

For a warehouse in Rotterdam or a distribution centre in Durban running single-shift operation, the 4 × 6-EVF-100 build at 4,800 Wh and 126.0 kg is usually the correct starting point; for a two-shift operation in Chennai or São Paulo with a fast turn-around charge window, the 4 × 6-EVF-150 build with a 48V/30 A charger keeps the published ≤ 4 hour charge acceptance intact. The wider AGM range behind these units is indexed on the CHISEN AGM battery page.

§4 — The Framework

Seven checks turn a 48V forklift battery enquiry into a pack that fits the bay, the charger and the duty cycle.

1. State the unit model, not just the pack voltage. Write “4 × 6-EVF-100 in series” rather than “48V 100Ah forklift battery”. The unit code determines the case dimensions, the weight, the terminal type and the published charge current, and none of those can be derived from the pack label.

2. Confirm the capacity rate and cut-off. The published rating is C3 to 1.75 V/cell. A second table on the same pages quotes 400-650 cycles against the 350-600 cycle figure, so ask which figure is being quoted and on which basis before comparing two suppliers.

3. Derive the charger from the cell, not the pack. The pack current equals the unit current because the units are in series. 48V/20 A for the 6-EVF-100 build, 48V/30 A for the 6-EVF-150 build.

4. Check the physical envelope against the truck bay. Longest unit per build runs from 258 mm to 483 mm, and the 6-EVF-135 is 338 × 172 × 280 mm against the 6-EVF-150 at 483 × 170 × 240 mm. Measure the bay, not the catalogue.

5. Do the weight arithmetic against the truck. 75.2 kg, 102.8 kg, 126.0 kg, 160.0 kg, 180.0 kg and 194.0 kg for the six builds. The 118.8 kg spread between the smallest and the largest pack is the difference between a truck that stays within its rated envelope and one that loses stability with a raised load.

6. Write the set points to the volt. 54.0 V float and 56.4 V equalisation across the 48V pack, which is 13.5 V and 14.1 V per 12V unit and 2.25 V per cell in float. Put them in the charger configuration table and in the maintenance schedule.

7. Plan the charging environment. The published working range is −15 °C to 50 °C and storage is −20 °C to 45 °C. Charge on a cooled battery, out of direct sun, in a ventilated alcove, and agree a named laboratory for the arrival capacity test on shipments into Santos, Jebel Ali, Lagos or Port Said.

§5 — The Trust

The 6-EVF range is produced inside a manufacturer that operates 8 production bases with an annual capacity of 70 million kVAh, under a quality management system certified to ISO 9001 with ISO 14001 covering the environmental system, and with CE, RoHS, REACH, MSDS and IMDG documentation for the destination market. The product pages for these units carry the full physical data and the GB/T 32620.1-2016 and GB/T 32620.2-2016 compliance references for lead-acid batteries for electric road vehicles, with JB/T 2599 referenced, and the wider AGM range is indexed on the CHISEN AGM battery page.

Two things deserve emphasis before a fleet purchase is committed.

First, the standards quoted here are checkable, and they are more useful than a generic CE mark. GB/T 32620.1-2016 and GB/T 32620.2-2016 are the Chinese national standards for lead-acid batteries used in electric road vehicles, and they set the technical conditions and product-type definitions a traction battery is built against. Ask for the test report that references them, with the report number, the unit model and the date. A supplier who publishes a range, a certificate index and a per-model datasheet is answering a different question from one who publishes only a product listing.

Second, a float design life of 2-5 years and a cycle life of 350-600 cycles describe two different services, and a fleet’s real replacement interval is whichever is reached first under the actual duty. A truck that charges overnight and works one shift consumes float standby capability; a truck on two shifts with an opportunity charge consumes cycles. Write the duty pattern into the enquiry and ask the supplier which figure they will stand behind for it, because that is the number a fleet manager will be held to.

A third point is about the arrival of the goods. Published data is published data, but a delivered pack is also a physical assembly: four units of the same model and batch, matched at the terminals, with a float voltage check across all four and a capacity check on one unit from the pack before it goes into service. For shipments into Santos, Jebel Ali, Lagos or Port Said, agree that inspection and the laboratory that will repeat it before the truck goes onto the floor.

§6 — FAQ

Q1. What does a 48V forklift battery consist of? Four 12V traction batteries connected in series. Four 6-EVF-150 units give 48 V × 150 Ah = 7,200 Wh; four 6-EVF-100 units give 48 V × 100 Ah = 4,800 Wh; four 6-EVF-60 units give 48 V × 60 Ah = 2,880 Wh. Because the four units are in series, the pack voltage is 48 V and the pack amp-hour rating equals the rating of one unit, not the sum of four.

Q2. What size charger does a 48V forklift battery need? One rated at the unit’s published maximum charge current, because in a series pack the current passes through every unit. The published maximum charge current is 0.2 C on every unit in the range: 12.0 A for the 6-EVF-60, 20.0 A for the 6-EVF-100, 24.0 A for the 6-EVF-120, 27.0 A for the 6-EVF-135 and 30.0 A for the 6-EVF-150. A 48V/30 A charger therefore suits a pack of four 6-EVF-150 units. A charger rated at the sum of the four unit ratings would deliver four times the published maximum to every unit.

Q3. How much does a 48V forklift battery weigh? It depends entirely on the unit repeated four times: 4 × 18.8 kg = 75.2 kg for the 6-EVF-60 build, 4 × 25.7 kg = 102.8 kg for the 6-EVF-80, 4 × 31.5 kg = 126.0 kg for the 6-EVF-100, 4 × 40 kg = 160.0 kg for the 6-EVF-120, 4 × 45 kg = 180.0 kg for the 6-EVF-135 and 4 × 48.5 kg = 194.0 kg for the 6-EVF-150. Use those figures for the truck’s balance and the floor loading, not for a generic 48V pack.

Q4. How long does a 48V forklift battery take to charge? The published charge acceptance is 80% charge in ≤ 4 hours, with a charger at the unit’s maximum charge current, and the charger itself should have a pulse function and temperature compensation, adjusting the float charge time seasonally against a 25 °C reference. The full float set point is 54.0 V and equalisation 56.4 V across the 48V pack. Charging a battery that has just come off a warm truck is not recommended: the published guidance is to charge on a cooled battery and to keep charging out of direct sun and out of enclosed high-temperature spaces.

Q5. What is the difference between a C3 rating and a C10 rating? The rate at which the capacity is measured. The 6-EVF range publishes capacity at the 3-hour rate to a 1.75 V/cell cut-off, so the 6-EVF-100 delivers 100 Ah at C3. A C10 figure would be measured over ten hours to a lower cut-off and would normally read higher for the same cell. For a traction duty the 3-hour rate is the relevant number because the truck lifts under high current; for a standby duty the 10-hour rate is the relevant one. Never compare two quotations without the rate and the cut-off on both.

Q6. Can different capacities be mixed in one 48V pack? Not in a pack that has to be charged and balanced as one unit. Each unit in a series pack must be the same model, and ideally from the same production batch, because the units age together and the pack’s usable capacity is set by the weakest unit. Mix a 6-EVF-100 with a 6-EVF-120 and the pack will be limited by the smaller unit for the rest of its life, with the larger unit repeatedly over- or under-charged depending on which end of the string is being measured.

Q7. What temperature range can a 48V forklift battery work in? The published working range is −15 °C to 50 °C and the storage range is −20 °C to 45 °C. Self-discharge is ≤ 3% per month at 25 °C. A warehouse in Rotterdam or Durban sits comfortably inside that window; a covered dock in Chennai in May sits close to the upper end of the working range, and a bay in a cold store in Scandinavia approaches the lower end. Capacity falls outside the comfortable middle of the band, so the usable reserve in those conditions is lower than the nameplate figure and belongs in the sizing.

Q8. What should be on the purchase order for a 48V forklift battery? The unit model and quantity, the series connection, the capacity rate and cut-off voltage, the published maximum charge current, the charger rating and the float and equalisation set points in volts for the pack, the case dimensions and terminal type, the weight per unit and the derived pack weight, the duty pattern the fleet intends to run, the batch reference, the test report referencing GB/T 32620.1-2016 and GB/T 32620.2-2016, and the arrival inspection procedure with the named laboratory.

Expert Summary

A forklift battery 48V pack is four 12V units in series, and every number that matters is published unit by unit. The 6-EVF-60 publishes 60 Ah at C3 to 1.75 V/cell, 258 × 170 × 160 mm, 18.8 ± 0.2 kg and 12.0 A maximum charge current; the 6-EVF-100 publishes 100 Ah, 330 × 170 × 218 mm, 31.5 ± 0.2 kg and 20.0 A; the 6-EVF-120 publishes 120 Ah, 407 × 170 × 240 mm, 40 ± 0.2 kg and 24.0 A; the 6-EVF-135 publishes 135 Ah, 338 × 172 × 280 mm, 45 ± 0.2 kg and 27.0 A; the 6-EVF-150 publishes 150 Ah, 483 × 170 × 240 mm, 48.5 kg and 30.0 A. All of them float at 13.5 V and equalise at 14.1 V, which is 54.0 V and 56.4 V across the pack and 2.25 V per cell in float, and all of them publish a 2-5 year float design life with a 350-600 cycle life at 50-80% depth of discharge.

Four derived numbers settle most of the decisions. The pack energy is 48 V × Ah: 2,880 Wh for the 60 Ah build up to 7,200 Wh for the 150 Ah build. The pack weight is 4 × unit weight: 75.2 kg, 102.8 kg, 126.0 kg, 160.0 kg, 180.0 kg and 194.0 kg. The charger is 48V at the unit rating — 48V/20 A for the 6-EVF-100 build, 48V/30 A for the 6-EVF-150 build — because a series pack passes the same current through every unit. And the specific energy stays inside a narrow 36.0 to 38.3 Wh/kg band, which tells the buyer that a larger pack is heavier in proportion to what it stores rather than inefficient.

The buyer who writes the unit model, the capacity rate, the charger rating, the set points and the pack weight onto the order line has a specification that any qualified factory can quote against and any workshop can check at the dock in Rotterdam, Jebel Ali, Santos, Lagos or Chennai. That is a short document, and it is what separates a fleet purchase that fits the truck from one that arrives and does not.

Contact CHISEN

Send the truck class, the shift pattern, the bay dimensions, the required runtime per shift and the quantity to the CHISEN export desk, and you will receive a quotation built on the published model data, the current lead time and the certification documents for your destination market.

• Email: jack@chisen.cn or sales@chisen.cn
• WhatsApp: +86 131 6622 6999
• AGM range index: https://www.chisen.cn/en/AGMBattery/QTF.html
• 6-EVF-60 model page: https://www.chisen.cn/en/6-EVF-60/12V60Ah.html
• 6-EVF-100 model page: https://www.chisen.cn/en/6-EVF-100/12V100Ah.html
• 6-EVF-120 model page: https://www.chisen.cn/en/6-EVF-120/12V120Ah.html
• 6-EVF-135 model page: https://www.chisen.cn/en/6-EVF-135/12V135Ah.html
• 6-EVF-150 model page: https://www.chisen.cn/en/6-EVF-150/12V150Ah.html

Related reading on the CHISEN knowledge centre: traction battery duty-cycle sizing, AGM charge acceptance and equalisation scheduling, battery bay ventilation and temperature control, and fleet spare-unit matching procedures.

CHISEN Battery — AGM valve-regulated lead-acid traction batteries for electric forklifts, stackers, AGVs, golf carts and sightseeing vehicles. 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.

See Full Bio