[Music]
have you ever wanted the ability to
power virtually anything on a goal well
in this video I will show you
step-by-step how you can make a power
bank that can do just that with the
ability to power at least 7 devices this
power bank also features a removable
battery pack which can be replaced for
actual capacity the capacity of the
battery pack is 188 watt hours which is
more than five times the capacity of a
normal power bank the 18 650 battery
since power bank users are easily
founding things like old laptop
batteries so it is easy to get them for
free or very cheap and if you manage to
do that the total cost of the components
goes down to $60 which is two times
cheaper than anything commercially
closed for the output the power bank has
a 150 watt wall port that can power
anything from lights to fans to mini
fridges or even TVs the power bank also
has a DC port that is adjustable from 13
to 15 volts that is made for devices
that can accept DC directly like laptops
and some soldering irons with a maximum
power output of 120 watts the power bank
can powered mid-range gaming laptops
comfortably even a maximum load finally
the power bank also features four
standard USB ports with two having quick
charge 3.0 and if you forget your cable
the power bank also has a wireless
charging pad on the top the power bank
charges with a standard laptop charger
or USB C and optionally the power bank
also comes with RGB lighting so it can
look cool even in the dark all this
power comes in a size slightly larger
than a standard water bottle so I can be
easily carried around furthermore with
over voltage over discharge
short-circuit and
over-temperature shut down along with
the fully automatic cooling system the
power bank is very safe to use if built
correctly I will now show you the
step-by-step process of building this
power bank here are the time stamps for
each step in this video you can skip to
any of those steps if you want before
the rest of you here we go
for this project you will need a number
of different components as for always
other links and part files are in a
description for the output you will need
a 12 volt USB quick charge car adapter
and have already taken it out of its
case a 200 watt boost converter a 150
watt 12 volt inverter with two USB ports
and finally a wireless charging circuit
you will also need a step-down DC
converter with a constant current
feature this is for charging the
batteries and two more mini DC step-down
converters a 3s lithium-ion battery
management circuit with balanced
charging the board also has over current
over discharge and short-circuit
protection to switch the high currents
you will need this isar a 12 volt DC
relays that can handle up to 20 amps you
will also need 2 5 millimeter DC jacks
60 by 10 millimeter 12 volt fan a
Schottky diode that can handle at least
5 amps a pair of xc60 connectors a 20
amp fuse seven of these three amp slide
switches if you want RGB on your power
bank
you'll also need 12 old RGB strips and a
3 button controller you will also need
22 18 and 12 gauge wires too many volt
meters half a millimeter thick copper
strips all the screws used in this video
are gonna be m3 flathead screws 5
millimeter aluminium heat sinks various
color 3 millimeter LEDs the temperature
control and protection are done through
these bi-metal temperature switches
these switches open or close and they're
rated temperature for this Powerbank
you will need for normally close 45
degrees type and through normally open
45 degrees
most importantly you will need 15 18 650
batteries you can use new or old cells
as long as they satisfy these three
conditions one they have roughly the
same tested capacity - they have roughly
the same internal resistance 3 the
maximum discharge current of each cell
must be at least 5 amps finally you will
need to surly print all the files in the
description be aware that some
components must be printed in PT g or
abs plastic here is the overall
schematic of the power bank it is
separated into seven systems they are
the battery pack the charging circuit
the AC inverter the DC step-up converter
the USB over-temperature protection
circuit the wireless charging circuit I
am finally the automatic cooling system
with RGB in a description I also
included the cat assembly of this power
bank if you wonder how the power bank
comes together you can download the
model and see for yourself I also
included a version without USB C and the
version without RGB the first step to
building this power bank is making the
removable battery pack to start get the
test at 15 18 650 batteries I am using
the model NCR 18 650 B for its high
capacity but if you want to bring this
on a plane use cells that are less than
1800 milliamp hours or use fewer cells
in each parallel group measure each cell
to make sure that they are at the same
voltage if not charged or discharged
theirselves until all 15 cells have the
same voltage now get the 3d printed
battery holder and insert the battery
with the positive on the side and
negative in the middle this creates a
configuration that looks like this
after all the batteries are inserted
press on the cap and secure it with six
screws before the front two screws are
secured slightly in the BMS like this
now cut four strips of half millimeter
thick copper sheet that a 7 millimeters
wide
this is what's going to carry the large
current from the batteries you can also
use brass or nickel strips if you have
them bend and cut the copper strips to
length
now get your iron as hot as possible and
tin the copper strips now solder the
batteries to the copper strip make sure
you never spend more than three seconds
per solder connection and only resold
her after the joint cools down when the
soldering is done the power pack should
look something like this solder the
strips to the BMS next solder short 12
gauge wire to xt60 connector and place
and solder the xt60 in the holder of the
battery pack then glue the xt60 in place
make sure that it is straight and flush
with the surface you can add a heatsink
onto the MOSFETs but this is optional
now it's time to test the battery pack
to make sure that it is safe to use
first add a heatsink
onto the converter then connect it to
the input of a power supply that is
above 14 volts then connect the output
to a meter that measures voltage and
amperage adjust the output to 12 point 6
volts next short the output so the
converter goes into constant current
mode and then adjust the output anywhere
between 2 to 3 point 5 amps depending on
how fast you like your batteries to get
charged then connect the output of the
meter to the power pack the battery
should begin charging as soon as the
blue light turns on closely monitor the
voltage and temperature of each cell if
there's a deviation of 0.2 volts or a
cell gets noticeably hotter than the
other cells stop the charging process
immediately and check the soldering
connection or replace the cell when the
light turns green the charging process
is finished now the second test is the
discharge test first connect the battery
to an input of a amp meter then get
something that uses 12 volts and draws a
lot of power in this case I am using my
100 watt flashlight I made a video about
how to make this flashlight check it out
if you're interested any
put at least 10 amp load onto the
battery for 20 minutes during this time
closely monitored the voltage and
temperature of the battery pack pay
special attention to solder joints as
improper joints can heat up quite
quickly after repeating these two tests
two more times we can move on to making
the locking mechanism first get the 3d
printed parts and a hinge using the
hinge mount to the pole tap onto the
base the hinges in this video are too
small so later on I switched them all
for larger ones next screwing the
locking ring and adding the locking
shims finally add on the lid and screw
the assembly onto the back of the
battery pack the battery pack is now
complete
you can make as many of these battery
packs as you want as long as you have
enough batteries this way if 188 watt
hours is not enough you can just slide
in another pack the next step is to make
the charging circuit here is the overall
schematic and this is how it works when
no power is connected the current can
flow through a normally closed contact
of the relays and to the output but when
power is connected the current flow
through the step-down converter with
constant current but then it is stopped
at the relay at the same time current
flows through the mini step-down
converter this turns down the cooling
fan and the two relays now the current
from the step-down converter with
constant current can flow into the
batteries now the output is switched off
this way the batteries are protected
from being charged and discharged at the
same time first we need to make
additional modifications to the
step-down converter de-solder the screw
terminals and the LEDs then at a
Schottky diode facing into the input
next solder thin wires to the LED pads
now get a 3d printed base and screw in
the step-down converter then solder the
input of the Stefan converter to the 5
millimetre DC jack if you want to charge
the power bank with USB C then you will
need to buy a small USB C 20
trigger and solder aid in parallel with
the DC jack the next step is to solder
three millimeter green red and blue LED
to the wires and test them to see if
they still work then mount them on the
side in order from top to bottom of
green blue then red the next step is to
get a mini step-down converter and
adjust its output voltage to 12 volts
and then solder it to the DC jack now
place two relays in this orientation
solder a 45 degrees normally-closed
temperature switch in series with the
input this switch extends into the
battery compartment this way if the
battery gets too hot the circuit
automatically stops the charging process
next solder the to relay coils in series
with the output of the mini step-down
converter solder the output of the
step-down converter to the normally open
contacts of the relays then solder a
thick 12 gauge wire 90 degrees to of
xt60 female connector then solder on a
20 amp curfews and wrapped the contacts
to insulated solder a tall gauge wire to
the negative terminal attached the xt60
connector to the holder on the base
solder the positive wire to both common
contacts of the relay cut and tinned the
ground wire next slide on a battery pack
connected to power the blue LED should
lights up as the battery begins charging
this indicates that the charging circuit
is now complete now we can move on to
the inverter circuit first take the
inverter circuit out of its case and
keep the screws because we will need it
for later disconnect is 30 millimeter
fan and the outlet glue and solder the
fan to the slot next to the mini
step-down converter if you remember the
last power bank I made you will remember
that the inverter has heat sinks on the
power MOSFETs well that's not the case
with this inverter so we need to make
our own heat sinks I simply bent two
pieces of copper sheets
and thermo epoxied them unto small
heating's then I saw more epoxies them
on to the MOSFETs on one of them I
attached a 45 degree normally open
temperature switch also by the way wrap
all thermal searches in tape because
they are not isolated and here's what
the finished assembly looks like before
adding in the inverter sliding a relay
into the base like this then solder a 12
gauge wire across the three relays like
this then carefully sliding the inverter
soldered a positive input of the
inverter to the normally open pin of the
relay then soldered a ground wire of the
inverter to the ground wire of the xt60
solder a switch to one of the coil pins
of the relay and solder the other coil
pin to the ground with this the base is
now finished now we can move on to the
middle layer first unscrew the boost
converter and take care out of its case
then desolder the screw terminals the
potentiometer and the AED replace a
small SMD LED with a three millimeter
one and now use longer wires to extend
the potentiometer solder a 18 gauge wire
to the output then slightly in a boost
converter onto the 3d printed middle
layer I use a screw to secure it
slightly potentiometer in this
orientation into the middle layer then
get the 3d printed voltmeter and switch
bracket adding a voltmeter and a switch
and solder them in series now solder and
glue a DC jack on to the output of the
boost converter glue on the voltmeter
and switch and solder a in parallel with
the output of the boost converter then
press in a relay in this orientation
solder the normally open pin of the
relay to the input of the boost
converter then solder a switch to one of
the coil pins then get the 3d printed
adjustment knob and insert a piece of
0.5 millimeter copper sheet into it
glue the stopper on to the other side
and make sure the knob can spin freely
carefully line up and glue the
adjustment knob onto the middle layer
now as the knob is turned the
potentiometer turns with it and the
voltage can be adjusted this way next
desalted our LEDs on the quick charge
converter and replace it with a three
millimeter green LED then desalter the
contacts on the board cover the contacts
on the back with Kapton tape and thermal
epoxy on small heat sinks along with a
normally open 45 degrees temperature
switch okay I have to stop the video
right here
because I forgot to film a step and that
is to solder two wires to the positive
and ground pin of the USB these two
wires are for the wireless charging
circuit then press and glue the USB
assembly onto the board next thermo
epoxy on another normally-open
45-degree thermal switch on to the
heatsink of the boost converter then
solder the to thermal switches in
parallel next add another switch on top
of the switch for the boost converter
solder one switch wire to the positive
of the USB converter and the other wire
to the coil pin of the relay by the end
you should have a pair of wire from the
USB output a pair of wires from the to
thermal switches in parallel and another
pair of ground wires then insert a 45
degree normally closed thermal switch to
the bottom of the assembly before adding
on the middle layer assembly thermal
epoxy a 45 degree normally open thermal
switch next to the inverter relay and so
due to thermal switches in parallel
alright it is time to put the two layers
together carefully place on a middle
assembly solder the 12 gauge output wire
from the relays to the input of the
relay on the middle layer and attach the
two ground wires to the ground wire of
the xt60 the next step is the automatic
cooling system
for this step locate the two pairs of
wires from the temperature switches
solder one side of the parallel
connection directly to the input of the
relays in other words they are connected
directly to the battery so the cooling
system would always stay active
now get the sixty by ten millimeter fan
and optionally another mini DC step down
converter the purpose of this converter
is to adjust the fan speed since the 12
volt fan I have is too fast and noisy
for my case I soldered the output of the
boost converter to the fan then I solder
the other pair of wires from the thermal
switches on to the input of the
step-down converter connect the
step-down converter to ground the next
circuit is the relay power system and
the USB converter circuit this is the
overall schematic basically the current
flows through the battery and passes
through the relays then the current
passes through two 45 degree normally
called thermal switches then the current
can flow through three components in
parallel they are the inverter relay the
boost converter relay and the USB
converter this is also the over
temperature protection system if either
of the thermal switches detects the
temperature of above 45 degrees
no relays can be turned on so the output
of the Powerbank shuts off first
soldered a 45 degree normally closed
thermal switch to the 12 gauge wire from
the output then connect the switching
series with the other normally closed
thermal switch which was mounted under
the middle there earlier in the video
next solder the output of the thermal
switch in parallel was the USB converter
switch and with the two other relay
coppens that have not been used now it
is very important to test the circuit to
make sure that all systems are working
properly
first connect all volts power to the
xc60 connector and flip on all the
switches as you can see all the output
circuits turns on now let's test the
over temperature protection circuit
first I set the temperature of my
soldering iron to a hundred degrees then
pressed a onto the normally closed
thermal switch after a few seconds well
the output turns off
and only turns out after the switch has
cooldown now I load each circuit to the
maximum amount and wait to see if the
cooling fan turns on and indeed the
cooling fan does turn on with all the
testing done you have just made it
through the most complex part of the
assembly now you can screw on the middle
assembly onto the base with five screws
then glue the cooling fan on to the side
the final part of the electronics
assembly is the top layer first mount a
voltmeter and switch on to the top
assembly then connect them in series
next get the RGB controller and desolder
the output connector and then mount a
small switch in this location then glue
the RGB controller next to it and solder
air in series with the switch then
solder the RGB controller in parallel
with a voltmeter next sliding a wireless
charging circuit and glue in place then
solder a switch in series with the
wireless charging circuits micro USB
input the next step is to solder the
four control wires to the RGB controller
and connect them to the color RGB strips
on the back then solder the breakout
pins to the last RGB strip I made for
more RGB strips and connected them with
wires in between and mounted them in the
grooves of the battery compartment next
we can put a top layer onto the assembly
solder the RGB voltmeter system directly
to the output of the batteries then
using a large heat shrink tubing
insulate the ground wire then connect
the wires from the USB output to the
input of the wireless charging switch
then screw on the top lid with four
screws the next step is to attach the
battery compartment you should have the
to thermal switches and the RGB cable
sticking out of the back connect the RGB
cable and slide on the battery
compartment and then press the two
thermal switches into the grooves secure
the battery compartment in place with
eight screws
sliding a battery to make sure
everything lines up the next step is to
get a 3d printed IO shield the IO shield
was printed with 0.2 millimeter nozzle
with a filament swap so I asked two
different colors fill the LED hose with
hot glue to diffuse the light then
insert the AC outlet into the IO shield
and glue it in place next glue the
inverter switch next to the two USB
ports then connect the AC port to the
inverter board screw in the i/o shield
with screws salvaged from the inverter
earlier in the video next get your 3d
printed sleeve sliding the assembly into
the outer sleeve the secure in place
with screws on both ends glue the RGB
controller cover on and add on the
stickers finally get the 3d printed end
caps I printed them out of ninjaflex so
it is flexible and is able to absorb
shocks and impacts the cap is glued on
with double-sided sticky tape this way
it can be removed if needed and with
that the Powerbank is finally complete
thank you very much for staying with me
through the whole process the power band
can be used for emergency backup power
for outdoor camping or anytime you need
portable power on the go so that's it
for this project if you liked it please
give this video a like and consider
subscribing to my channel for more DIY
projects like this I'll leave you with
montage of this Powerbank in all its RGB
glory and as for always thanks for
watching
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[Applause]