BiXPower 42V 3A AC Charger for
36V Lithium-Ion Batteries
Professional 126W maximum-output
lithium-ion battery charger for
compatible 36V nominal
10S rechargeable battery packs.
The BiXPower ACC-36V3A is a
dedicated AC-to-DC lithium-ion
battery charger designed for
compatible 36V rechargeable
lithium-ion battery packs.
It provides a maximum charging
voltage of 42.0V DC and a
maximum controlled charging
current of 3.0A.
Unlike a conventional
constant-voltage laptop
power adapter, this charger
is designed to manage battery
charging using a
constant-current /
constant-voltage (CC/CV)
charging profile.
The ACC-36V3A is suitable for
compatible 10-series-cell (10S)
lithium-ion battery packs,
including BiXPower BX3691
and BX3699 batteries when
their charging specifications
and connector polarity match.
Key Features
-
Designed for compatible
36V nominal 10S
lithium-ion batteries
-
42.0V maximum charging voltage
-
3.0A maximum charging current
-
126W maximum rated output power
-
Constant-current /
constant-voltage (CC/CV) charging
-
Red and green LED charging indicator
-
5.5mm OD x 2.1mm ID
DC barrel output connector
-
Universal 100-240V AC input
-
Suitable for compatible
rechargeable battery packs
-
One-year limited warranty
42V 3A Lithium-Ion Battery Charger
for 36V Rechargeable Batteries
BiXPower 42V 3A AC battery charger
for compatible 36V nominal
10S lithium-ion battery packs.
The ACC-36V3A provides a
maximum charging current
of 3A, making it suitable
for compatible 36V lithium-ion
battery packs that support
this charging rate.
Compared with a lower-current
charger, a 3A charger may
reduce charging time for
larger batteries, provided
the battery manufacturer
permits charging at 3A.
The charger automatically
controls charging current
and voltage according to
its charging profile.
Its rated 3A output represents
the maximum controlled
charging current, not a
fixed current throughout
the entire charging cycle.
Compatible 36V Lithium-Ion Batteries
This charger is intended
for compatible lithium-ion
battery packs with ten
series-connected cell groups,
commonly described as
10S lithium-ion batteries.
These batteries typically have:
-
Nominal battery voltage:
36V
-
Full-charge voltage:
42.0V
-
Battery chemistry:
Conventional 4.2V-per-cell
lithium-ion chemistry
-
Maximum permitted charging
current of at least 3A
-
Compatible DC charging
connector and polarity
This charger may be used
with compatible BiXPower
BX3691 and BX3699 batteries
when their charging input
requirements match the
ACC-36V3A specifications.
Important Battery Compatibility Information
Not every battery labeled
"36V lithium battery"
uses the same chemistry
or charging voltage.
Do not use this charger
for 36V LiFePO4 batteries,
lead-acid batteries,
or lithium-ion batteries
that require a different
charging voltage.
The battery must be designed
to accept a 42.0V CC/CV
charger with up to 3A
charging current.
5.5 x 2.1mm DC Output Connector
DC barrel output connector:
5.5mm outside diameter,
2.1mm inside diameter.
The ACC-36V3A uses a
DC barrel output connector
with the following dimensions:
-
Outside diameter (OD): 5.5mm
-
Inside diameter (ID): 2.1mm
-
Connector barrel length:
approximately 12mm
Before ordering, verify
that the connector size
and polarity match your
battery's charging input.
A connector that physically
fits does not necessarily
indicate electrical
compatibility.
A 5.5 x 2.1mm connector
is different from a
5.5 x 2.5mm connector.
Please verify the
inside diameter carefully.
LED Charging Status Indicator
The ACC-36V3A includes
an LED indicator to help
identify charging status.
The indicator's behavior
between 200mA and 300mA
is not specified.
A green indicator may also
appear when the charger
is disconnected from
the battery or when
the battery is not
accepting charging current.
Follow the battery
manufacturer's instructions
to confirm charging completion.
Battery Charger vs. Regular
Constant-Voltage Power Adapter
A lithium-ion battery charger
may look very similar
to a laptop AC-to-DC
power adapter.
Both convert household
AC electricity into DC power.
However, they are designed
for different purposes
and behave differently
when connected to a load.
1. Lithium-Ion Battery Charger:
Controlled Charging Current
and Voltage
A dedicated lithium-ion
battery charger controls
both charging current
and charging voltage
according to the battery's
charging requirements.
Most conventional lithium-ion
battery chargers use a
constant-current /
constant-voltage (CC/CV)
charging process.
Stage 1: Constant-Current Charging
During the main charging stage,
the charger supplies a
controlled charging current,
up to its rated maximum
of 3A.
As the battery charges,
its cell voltage gradually
increases.
The charger adjusts its
output voltage to follow
the battery voltage while
maintaining the controlled
charging current.
The output voltage gradually
rises toward the specified
maximum charging voltage
of 42.0V.
Stage 2: Constant-Voltage Charging
When the battery reaches
the specified final charging
voltage, the charger maintains
approximately 42.0V.
During this stage,
charging current gradually
decreases as the battery
approaches full charge.
Stage 3: Charging Completion
As charging current decreases
to the charger's completion
threshold, the charger
indicates that charging
is complete or nearly complete.
For the ACC-36V3A,
the LED turns green
when output current
falls to 200mA or less.
Important:
The charger's rated 3A
output current is its
maximum controlled
charging current.
It does not mean that
the charger continuously
delivers 3A throughout
the charging cycle.
2. Regular Laptop AC Power Adapter:
Constant-Voltage Output
A conventional laptop
AC-to-DC power adapter
is designed to supply
a constant DC output voltage,
such as 19V, 20V, 24V,
or another specified voltage.
The adapter maintains its
rated output voltage while
the connected device draws
the current it needs,
up to the adapter's
maximum output capacity.
For example, a regular
24V 5A power adapter
provides approximately
24V constant-voltage output.
The connected device
may draw 1A, 2A, 3A,
or 5A depending on
its power demand.
The adapter's 5A rating
represents its maximum
available output current.
It does not mean that
the adapter always
outputs 5A.
Battery Charger vs. Power Adapter:
Comparison
Why You Should Not Use a Regular
Laptop Adapter to Charge
an Unprotected Lithium-Ion Battery
Lithium-ion battery cells
have relatively low
internal resistance.
If a battery is connected
directly to a constant-voltage
power source without suitable
charging control, excessive
charging current may flow.
A conventional power adapter
is generally designed to
maintain its rated voltage
while supplying the current
requested by the connected
load, within its output limits.
Without appropriate charging
control, excessive current
may cause:
- Battery overheating
- Battery cell damage
-
Accelerated battery aging
and capacity loss
-
Power adapter overload
or shutdown
-
Damage to charging cables
and connectors
-
In severe cases,
thermal runaway or fire
Battery Charging Safety Warning
Never connect a regular
constant-voltage laptop
power adapter directly
to lithium-ion cells
or a battery pack that
lacks a suitable charging
controller.
A battery management system
(BMS) or protection circuit
alone does not necessarily
provide the charging-current
control and charge termination
needed for safe charging.
When Can a Regular AC Power Adapter
Charge a Lithium-Ion Battery?
Some rechargeable battery packs
include a built-in charging
controller that manages
the charging voltage
and current delivered
to the battery cells.
For these battery packs,
a compatible constant-voltage
AC-to-DC power adapter
may be used as the external
charging power source.
The internal charging controller
regulates the battery charging
process rather than relying
on the external adapter
to provide the complete
charging profile.
Before using a regular
AC power adapter,
verify that:
-
The battery explicitly
supports charging from
a constant-voltage DC source.
-
The adapter output voltage
is within the battery's
specified charging input range.
-
The adapter provides
sufficient output power.
-
The connector size
and polarity are correct.
-
The battery has appropriate
internal charging control.
Some BiXPower batteries,
including models with
built-in charging controllers,
can accept compatible
external DC power adapters.
However, this capability
must be verified for each
individual battery model.
Helpful Technical Tip
If a rechargeable battery
accepts a relatively wide
range of DC charging input
voltages, it may indicate
that the battery includes
internal power conversion
or charging control circuitry.
Always check the battery's
official specifications
before using an ordinary
power adapter.
Why Charging Current Matters
for Battery Life
Lithium-ion batteries should
be charged within their
manufacturer-specified
current limits.
Moderate charging currents
generally help reduce
heat generation and
battery cell stress.
Charging at higher currents
may reduce charging time
but can also increase
battery temperature
and long-term aging.
The ACC-36V3A provides
up to 3A charging current.
It is intended for
battery packs whose
charging specifications
permit this level.
For smaller batteries
or battery packs with
lower recommended charging
currents, a lower-current
charger may be more appropriate.
Technical Specifications
How to Charge a Compatible
36V Lithium-Ion Battery
-
Verify compatibility.
Confirm that the battery
requires a 42.0V CC/CV
charger and permits
charging current up to 3A.
-
Check the connector.
Confirm the battery charging
port accepts the charger's
5.5 x 2.1mm DC connector
with matching polarity.
-
Connect the DC output.
Insert the charger connector
into the battery's designated
charging input port.
-
Connect AC power.
Plug the charger into a
suitable 100-240V AC outlet.
-
Monitor charging.
The LED normally turns
red during active charging.
-
Check completion.
The LED normally turns
green when output current
falls to 200mA or less.
-
Disconnect after charging.
Follow the battery
manufacturer's charging
and disconnection instructions.
Charging Precautions
-
Charge batteries in a
dry, ventilated area.
-
Keep the charger away
from water and moisture.
-
Do not cover the charger
during operation.
-
Do not charge damaged,
swollen, or overheated batteries.
-
Do not exceed the battery's
maximum permitted charging current.
-
Do not use the charger
with incompatible battery chemistries.
-
Stop charging if abnormal
heat, odor, or behavior occurs.
Frequently Asked Questions
Can I use this charger
for any 36V lithium battery?
No. The battery must require
a 42.0V final charging voltage,
support up to 3A charging current,
and have compatible connector
dimensions and polarity.
Is this charger compatible
with 36V LiFePO4 batteries?
No. LiFePO4 batteries generally
require a different charging
voltage and charging profile.
Use a charger specifically
designed for the battery.
Does the charger always
output 3A?
No. The 3A rating is the
maximum controlled charging
current. Charging current
normally decreases during
the constant-voltage stage.
Why does a 36V battery
need a 42V charger?
A conventional 10S lithium-ion
battery has a nominal voltage
of approximately 36V.
Each cell group reaches
approximately 4.2V at
full charge, giving a
10S full-charge voltage
of 42.0V.
Can I use a regular
36V power adapter instead?
Not for direct charging
unless the battery includes
a suitable internal charging
controller and explicitly
supports that adapter.
A conventional power adapter
does not necessarily provide
the charging current control
and termination required
by lithium-ion cells.
Does a 3A charger charge
faster than a 1.5A charger?
It may charge faster if
the battery supports
a 3A charging rate.
Actual charging time
depends on battery capacity,
state of charge,
temperature, and the
constant-voltage charging stage.
What does the green LED mean?
The green LED indicates
charger output current
is 200mA or less.
This normally occurs
near the end of charging,
but may also occur when
no charging current
is flowing.
What is the output connector size?
The ACC-36V3A uses a
5.5mm outside diameter
x 2.1mm inside diameter
DC barrel connector.
What is the warranty?
The ACC-36V3A includes
a one-year limited warranty.
Package Contents
-
1 x BiXPower ACC-36V3A
42V 3A AC Battery Charger
-
1 x Compatible AC Power Cord
BiXPower Technical Support
Not sure which charger
is suitable for your
rechargeable battery?
Contact BiXPower with
your battery model number,
required charging voltage,
maximum charging current,
connector dimensions,
and polarity.
Our technical support team
can help identify a
compatible charging solution.
Product Code: ACC-36V3A
Maximum Charging Output:
42.0V DC / 3.0A
Output Connector:
5.5 x 2.1mm
Warranty: One Year
