A correctly selected PolyBat (LFP) battery for warehouse equipment can reduce energy costs by more than 50 per cent and, in the long term, lead to a significant reduction in the costs of purchasing and replacing batteries.

How do you choose the right capacity for a PolyBat lithium-ion battery so that a single charge is sufficient for the planned workload?

Let’s look at a few scenarios for the intensity of warehouse equipment use.

1. Low-intensity operation (2–3 hours per shift)
We will calculate the capacity using the formula:

Lithium-ion battery capacity = Acid capacity (max.) × 0.6
Selection of charging current = (Battery capacity) / 2

Let’s use an example to calculate this. We need to determine which lithium-ion battery to choose for a 1.5-tonne forklift truck with a 48V/510Ah lead-acid battery.
Capacity of the lithium-ion battery = 510 × 0.6 = 306Ah.

In other words, for a 1.5-tonne forklift truck with an operating intensity of 2–3 hours per shift, a capacity of 304Ah for the PolyBat lithium-ion battery will be sufficient. 16 LFP-304Ah.

We calculate the required current parameters for the charger: 304Ah/2 = ElPulsKar-LFP 48V 150A charger

Forklift truck for use in and outside the warehouse

2. The average operating time of a forklift truck is around 5 hours per shift.
Lithium-ion battery capacity = lead-acid battery capacity × 0.7. Selection of charger current = (battery capacity) / 2.

Using the same example, we will calculate the required battery capacity for a 1.5-tonne electric forklift with a 48V/480Ah lead-acid battery.
Capacity of the PolyBat lithium-ion battery = 510 × 0.7 = 357Ah (the 410Ah PolyBat is the closest capacity).

In other words, a 1.5-tonne forklift truck operating for 5 hours per shift will require a PolyBat 16 LFP-410Ah lithium-ion battery.

We calculate the correct current parameters for the charger for this battery as 410 Ah / 2 = 205 A (charger current), but an ElPulsKar-LFP 48 V 200 A charger will also be perfectly adequate.

3. High workload (6–7 hours out of an eight-hour shift)
If the forklift is expected to be in use for almost the entire shift, the capacity of the required lithium-ion battery can be calculated using the following formula: Capacity of the PolyBat lithium-ion battery = Capacity of the lead-acid battery × 0.8–0.9
Selection of charger current = (Battery capacity) / 2

In our example, for a 1.5-tonne forklift with a 48V/510Ah lead-acid battery, a PolyBat lithium-ion battery with a capacity of 450Ah is required.
Calculation: Lithium-ion battery capacity = 480 × 0.9 = 459Ah (460Ah – the closest PolyBat battery capacity is the 16 LFP-460Ah)
Charger parameters = 460Ah / 2 = 230A (charger current), but the ElPulsKar-LFP 48V 200A charger is also suitable.

These calculations will help you work out the required capacity yourself when selecting and ordering, and you can also contact our qualified staff on: +359 897881607359 897881607, +359 897881604 ; email: sales@polybet.bg