As a key handling tool, the performance of forklift directly affects the operational efficiency. And in the electric forklift system, the battery plays a vital role. Choosing the right size of forklift battery not only affects the running time of the equipment, but also relates to the stability and service life of the whole vehicle. So, what are the determinants of forklift battery size? Capacity (Ah) and voltage (V) are the two core elements.
Positive correlation between capacity and cell size
Battery capacity (in Ah) represents the total amount of energy it can store under specific discharge conditions. The capacity increase of lead-acid batteries needs to be realized by the following physical adjustments:
Increase in the number of plates: For every additional pair of plates, the capacity is increased by about 15-20Ah, but it will lead to an increase in the length of the battery by 3-5cm.
Expansion of electrolyte volume: For every 100Ah increase in capacity, the electrolyte volume needs to be expanded by 5-8L, which corresponds to a 2-3cm increase in battery height.
For example, the typical size of a 24V/400Ah battery is 800mm long x 500mm wide x 600mm high, while the size of an 800Ah battery with the same voltage will increase to 1,200mm long x 600mm wide x 800mm high, with an increase in weight of about 65%.
Remodeling of Battery Structure by Voltage Rating
1. Voltage in series with individual cells
Lead-acid batteries have a single unit voltage of 2V and are connected in series to achieve the target voltage:
A 24V system requires 12 monoblocs and is compact, with common dimensions of 700-900mm in length.
80V high-voltage systems require 40 cells, with cell lengths typically exceeding 1500mm, and require additional design of arc-proof isolation layers.
2. Space Challenges for High Voltage Systems
48V and above batteries are often stacked in layers due to the increase in the number of cells in series:
Single cell spacing needs to be ≥5mm to prevent thermal runaway, resulting in a 10-15% increase in width.
High-voltage connections take up 20% more space than low-voltage systems, requiring an 8-10cm wiring zone at the top of the battery.
Dimensional standards and installation compatibility
Forklift manufacturers usually reserve a dedicated compartment for batteries, so battery dimensions must be closely matched to the equipment. Common battery size standards include DIN (German Industrial Standard) and BS (British Standard), each covering a specific size range and pole layout.
When replacing or purchasing batteries, it is recommended to match the forklift brand and model to avoid inability to install or safety hazards due to size discrepancies. Maintenance space and ease of battery replacement should also be considered.
In general, the size of a forklift battery is not set arbitrarily, but is determined by a combination of capacity, voltage, battery type and equipment structure. When selecting a battery, it is important to meet the operational requirements while taking into account the physical size of the battery and its compatibility with the forklift. Reasonable selection of capacity and voltage level will help to improve the overall performance of the forklift, prolong the service life of the battery and reduce operating costs.