Battery charger circuit diagram
Battery charger circuit diagram - LM317 voltage regulator forms a constant
current source to provide 50mA charging current for the S01-S06AA battery box
array. Each battery box is connected in series with the LED and is connected to
a shunt resistor. When the battery case contains a battery, the LED lights up
during charging. Multifunctional battery charger (1)
The LM317 voltage regulator forms a constant current source to provide 50mA
charging current for the S01-S06AA battery box array. Each battery box is
connected in series with the LED and is connected to a shunt resistor. When the
battery case contains a battery, the LED lights up during charging. Each battery
box is connected in parallel with the LED through a 5.1V zener tube.
Battery charger circuit diagram (2)
There are two different opinions on whether alkaline batteries can be
charged. Some say it can be recharged and the effect is very good. Some say it
should never be recharged, as the battery instructions warn of the risk of
explosion. In fact, alkaline batteries are indeed rechargeable, and the number
of recharges is generally about 30-50 times.
In fact, it is due to the mastery of charging methods that leads to two
completely different consequences. First of all, there is no doubt that alkaline
batteries can be recharged. At the same time, in the battery instructions, it is
mentioned that alkaline batteries are not rechargeable and charging may cause
explosion.
This is true, but note that the word "may" cause an explosion. You can also
understand it as a disclaimer of self-protection statement from the
manufacturer. The key to charging alkaline batteries is temperature. As long as
the battery can be charged without high temperatures, the charging process can
be completed smoothly. The correct charging method requires the following
points:
1. Small current 50MA
2. Don’t charge 1.7V, don’t discharge 1.3V
After some people tried charging, they categorically said that they could
not charge. The reasons for problems such as no charging, short power use time,
leakage, explosion, etc. were mostly due to problems with the charger. If the
charging current of the charger is too large, it will far exceed 50ma. For
example, the charging current of some fast chargers is above 200ma. The direct
consequence is that the battery temperature is very high and it is hot to the
touch. It may leak or explode in serious cases.
Some people use nickel metal hydride rechargeable battery chargers to
charge. Low-end chargers do not have an automatic charging stop function.
Long-term charging may cause the battery to overcharge and cause leakage and
explosion. Better chargers have an automatic charging stop function, but the
charging stop voltage is generally set to 1.42V for nickel-metal hydride
rechargeable batteries, while the full voltage of alkaline batteries is about
1.7V.
Therefore, if the voltage is too low, it feels like it cannot be charged,
and the power usage time is short, and it has no effect. Another thing is that
not charging the battery means not waiting until the battery is completely dead
before charging. If you do this, no matter how good the battery is, it can only
be charged three or five times, and the effect is poor.
It is generally recommended to use Nanfu alkaline batteries with a voltage
of not less than 1.3V. Therefore, if you plan to charge alkaline batteries, you
must have a qualified charger with a charging current of about 50ma and a
charging cut-off voltage of about 1.7V. Take a look at your home charger.
There are special chargers for alkaline batteries on the market, so-called
patented products. In fact, it is a simple circuit with a charging voltage of
1.7V and a current of 50ma. Using the existing parts LM358 and TL431 on hand, I
made a simple circuit that automatically stops charging when the cut-off voltage
is 1.67V. The cost is only two yuan. For reference by interested friends.
Related instructions:
Alkaline manganese rechargeable battery: It is developed on the basis of
alkaline zinc manganese battery. Due to the application of mercury-free zinc
powder and new additives, it is also called mercury-free alkali manganese
battery. This kind of battery can be recharged and used dozens to hundreds of
times without changing the discharge characteristics of the original alkaline
battery, which is relatively economical and affordable.
Alkaline zinc-manganese battery, referred to as alkaline manganese battery,
was successfully developed in 1882, developed in 1912, and was put into
production in 1949. It was found that when KOH electrolyte solution is used
instead of NH4Cl as the electrolyte, there are major changes in both the
electrolyte and the structure, and the specific energy and discharge current of
the battery can be significantly improved.
Battery charger circuit diagram (3)
In the circuit, diodes D1 to D4 rectify the AC input, and capacitors C1 and
C2 filter the DC. L1, C1 and C2 form a π-type filter to attenuate differential
mode conduction EMI noise. Are these transformers E-sheild with
powerIntegrations? The combination of technologies allows this design to easily
meet the EN55022 Class B conducted EMI requirements with sufficient margin
without the need for Y capacitors. Fireproof, fusible, wire-wound resistor RF1
provides critical fault protection and limits inrush current generated during
start-up.
Figure 1 shows U1 powered by an optional bias supply, which reduces no-load
power consumption to less than 40mW. The value of bypass capacitor C4 determines
the amount of cable drop compensation. A value of 1µF corresponds to
compensation for a 0.3Ω, 24AWG USB output cable. (10µF capacitor compensates for
0.49Ω, 26AWG USB output cable.)
In the constant voltage phase, the output voltage is regulated by switching
control. The output voltage is maintained by skipping switching cycles.
Regulatory voltage can be maintained by adjusting the ratio of enable to disable
periods. This also allows the converter's efficiency to be optimized over the
entire load range. Under light load (trickle charging) conditions, the current
limit point is also reduced to reduce the transformer flux density, thereby
reducing audio noise and switching losses. As the load current increases, the
current limit point will also increase, and fewer and fewer cycles will be
skipped.
When no more switching cycles are skipped (the maximum power point is
reached), the controller within LinkSwitch-II switches to constant current mode.
When the load current needs to be further increased, the output voltage will
decrease accordingly. The drop in output voltage is reflected in the FB pin
voltage. In response to a drop in the FB pin voltage, the switching frequency
will decrease linearly, resulting in a constant current output.
D5, R2, R3 and C3 form an RCD-R clamp circuit to limit the drain voltage
spike caused by leakage inductance. Resistor R3 has a relatively large value to
avoid drain voltage waveform oscillation caused by leakage inductance. This
prevents excessive oscillation during turn-off, thereby reducing conducted
EMI.
Diode D7 rectifies the secondary and C7 filters it. C6 and R7 work together
to limit transient voltage spikes on D7 and reduce conducted and radiated EMI.
Resistor R8 and Zener diode VR1 form an output dummy load, which ensures that
the output voltage at no load is within acceptable limits and ensures that the
battery is not completely discharged when the charger is disconnected from the
AC mains. Feedback resistors R5 and R6 set the maximum operating frequency and
output voltage in the constant voltage stage.
Read recommendations:
14500 450MAH 3.7V
What is the reason why the customized capacity of lithium batteries is declining faster and faster?1
What does a power battery pack mean?
home energy storage lithium battery direct sales
CR2025 battery
360° FACTORY VR TOUR
Whatsapp
Tel
Email
TOP