2S 3S 4S 5S 6S 7S 8S 10S 13S 14S LiPo LiFePO4 LTO 1.2A LED Active Equaliser Balancer Equalizer

 

Even when building a battery pack with identical and well matched cells, the individual state-of-charge of a long string of cells will diverge over time and charge cycling. This is due to small variations in cell characteristics and localised operating conditions, which can lead to small differences in self-discharge and load current.

 

Equalising or balancing a multi-cell pack helps to maximize capacity and service life of the pack by working to maintain equivalent state-of-charge of every cell, to the degree possible given their different capacities, over the widest possible range. Equalising is only necessary for packs that contain more than one cell in series. Parallel cells will naturally equalise since they are directly connected to each other, but groups of parallel wired cells, wired in series (parallel-series wiring) must be equalised between cell groups.

 

Passive equalisation
With passive equalisation, energy is drawn from the most charged cell and dissipated as heat, usually through resistors.

This equalises the state of charge at some fixed point – usually either "top balanced", with all cells reaching 100% SOC at the same time; or "bottom balanced", with all cells reaching minimum SOC at the same time. This can be accomplished by bleeding energy from the cells with higher state of charge (e.g., a controlled short through a resistor or transistor), or shunting energy through a path in parallel with a cell during the charge cycle so that less of the (typically regulated constant) current is consumed by the cell. Passive equalisation is inherently wasteful, with some of the pack's energy spent as heat for the sake of equalising the state of charge between cells. The build-up of waste heat may also limit the rate at which equalisation can occur.

 

Active equalisation

With active equalisation, energy is drawn from the most charged cell and transferred to the least charged cells, usually through capacitor-based, inductor-based or DC-DC converters. Active balancing attempts to redistribute energy from cells at full charge to those with a lower state of charge. Energy can be bled from a cell at higher SOC by switching a reservoir capacitor in-circuit with the cell, then disconnecting the capacitor and reconnecting it to a cell with lower SOC, or through a DC-to-DC converter connected across the entire pack. Due to inefficiencies, some energy is still wasted as heat, but not to the same degree.

 

Principle of equalisation:
This module uses adjacent differential voltage equalisation through DC-to-DC converters. When the adjacent battery voltage difference reaches 0.1V or more, the internal trigger equalisation work is performed until the adjacent battery voltage difference is within 0.03V. There is adjacent voltage equalisation both when charging and discharging on the battery pack.

 

The LED is on to indicate that the corresponding two batteries are being balanced.

The LED is off, it means that the equalisation has been completed, or the voltage difference has not reached the starting conditions,

If the LED is flashing, it means that the equalisation has failed to start, either the cells are not close enough in specifications or there is a wiring fault.

 

Features:

·       High-precision energy transfer equalisation;

·       Exclusive equalization IC;

·       High current 1.2A energy transfer;

·       Constantly equalises the battery voltages;

·       Improves the overall battery pack efficiency;

·       Reduced battery maintenance costs.

Parameters:

·       Operating voltage range: 2.0V-4.5V.

·       Universal; suitable for LiPo, Li-Ion, LiFePO4 and LTO batteries.

·       Equalisation current: Adjacent voltage difference is 0.1V, the equalisation current is about 0.5-0.7A;

·       Adjacent voltage difference is above 0.2V, the maximum equalization current is 1.2A;

·       The smaller the differential voltage, the smaller the equalisation current.

 

For larger battery packs the modules can be daisy chained together.

 

Packing List:
1x 1.2A LED Active Equaliser (choose the number of cells above)
1x Balancing cable