build a 1s or 3.7 volt lithium ion battery pack

After trying many different unit configurations, I found a 3. 7 volt pack (
One without serial unit configuration)
Very simple and cheap.
This is simpler because you don\'t have to worry about the different cells being discharged at different speeds.
For example, in a 4S package, one unit may consume earlier than the other, leaving a lot of unused energy in the other unit.
You don\'t need to balance the cost with a 1 s package.
Cheaper because 1 s PCBs are much cheaper.
The only drawback of the 1 s package is the voltage range (2. 5 to 4. 2 volts)
Not as useful as higher voltages.
Nevertheless, I find this package very useful and in this manual I will show you how to make a package and how to use it.
This project assumes that you already know how to weld and splice wires.
In addition, lithium batteries can be dangerous if handled improperly.
Go to this page of my other instructable for a detailed warning of everything that might go wrong.
This is the pcb I use in batteryspace.
Even the highest rated current is only $2. 50.
The price is $21 compared to the cheapest 5S PCB.
Wiring is very simple.
The lead of the battery is on one side, the lead of the charging and traction power supply (
Share the same touch point)
On the other side.
I used European terminal blocks to make sure I only need to weld the PCB once.
Because the lithium ion battery is very unstable, PCB must be used to protect the battery. Lithium-
If the ion batteries overcharge or exceed the current limit, they may be destroyed or even on fire.
In my opinion, their most useful function is to prevent the battery voltage from falling below 2. 5 volts. Lithium-
If the ion batteries are allowed to discharge below 2, they are destroyed. 5 volts.
Once the lower limit is reached, the PCB will turn off the circuit.
If you short circuit, the PCB will turn off the circuit and will not turn on again unless you repair the short circuit and plug the charger into the power supply.
Also, the first time you put the package together, it may not work until you apply for 4.
Charging/power lead 2 V on PCB.
This may be necessary even if the battery is mostly charged. Applying 4.
2 volts will open the PCB.
The PCB can prevent the PCB itself from producing a short circuit, but it is still possible to cause a short circuit directly from the battery.
In this case, the PCB does not save the package.
Although many batteries can be charged at the same time by \"charging\" through the first battery, I do not recommend doing so.
It is not dangerous to do so, but what happens is that the battery close to the charger is first charged, and then the charger turns off once it is detected that the first battery has reached 4. 2 volts.
Other batteries under the line absorb the charge so slowly that they are not fully charged when the first one is charged.
Make sure there is a direct electrical path from the charger to each battery.
In the picture you will see 5 battery stands, 4 18650 each.
Later I thought there was too much juice so I took 3 packs.
This is the advantage of this package as I can customize it based on the capacity I need.
Riding a bike in town, I use 8 cells, but I may use all 20 cells during a long bike trip.
I just need a screwdriver to mark or remove the cell.
I separate the battery boxes with cardboard and plastic sheets to make sure they don\'t short.
Buy a smart charger
This is what you use.
It is designed for packaging for at least 6 amp hours.
My package is about 12 am hours.
It should take 2 hours to charge.
12 am p hour pack/6 amp charger = 2 hour charge time I cut the crocodile clips off the charger and attach them to the charging leads on the PCB.
I use this bag on my bike.
It powers my bike lights and my phone.
XM with light of 1300 lumens-L T6 C8.
It is powered by a lithium-ion battery of 18650.
I realized that I could weld the wires to the positive and negative contacts on the lamp and run from the external battery pack.
My external packaging has 8 18650 s in parallel so the lights can now last 8 hours instead of 1 hour full of electricity.
Another use is to charge my phone.
I found a small upgraded switch mode power regulator in Dimension engene.
It is perfectly designed to get 3 different outputs.
7 V nominal package and lift it to the 5 V required to charge the phone.
There is a way to charge your phone during long bike trips that is very useful.
When I use my phone\'s gps navigation, the battery runs out in 2 minutes. 5 hours.
With outfitting (
All 20 cells)
I can extend it to about 75 hours!
I will be cycling around the US this summer and I would like to use the gps log mobile app called \"My track\" to record every mile of my journey.
I will charge at restaurants and hostels whenever there is a chance.
This is easy to do as the package and charger are placed in my removable handle bag.