2S 3S 4S LiPo LiFePO4 LTO 1.3A 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.
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 1.3A;
· The
smaller the differential voltage, the smaller the equalisation current.
Connections:
For larger battery packs the modules can be daisy chained
together.
Packing List:
2S, 3S or 4S LiPo LiFePO4 LTO 1.3A Active Equaliser (choose the option above)