My DIY Lithium Charger
STEP BY STEP, HOW TO CHARGE.
IF THE BATTERY IS BALANCED IN THE FIRST PLACE.
Connect each balance wires to each 3in1 Battery Dischargers
Cycle through the settings, select discharge, and then set your desired voltage level. If you don't know how to use it, watch this video
Now plug in the battery to the boost converter.
Next is plug in the laptop power supply to the boost converter as shown below.
Power up the power supply
Now set the voltage in the boost converter.
Remember to match your total end voltage here with the discharge voltage you set in the discharger's.
Example. If you set the discharger's at 4.0 volts, then 13(s) x 4.0 volts = 52 volts.
Then use this value in your boost converter. This is critical.
Next is set the amperes.
Now make sure that you know your batteries max charge amps.
Normally I set it at 1.5 amps. The lower amps, the slower it charge. The slower it charge, the better.
If I am in a hurry, I set it to 2 amps.
I know for a fact that my batteries can accept 1C charge. So that is at 5 amps. So check your batteries recommended charge rate.
Once everything is set, then run the boost converter to start charging.
IF BATTERY IS OUT OF BALANCE
Then do not TOP BALANCE them at 4.0 volts or worst 4.1 volts.
Try to use the BALANCE mode first and let it balance at maybe 3.9 volts.
Once you have fully balanced it at that level. Then you can proceed to charging it again as mentioned above.
NOTE:
That this booster is a CC/CV converter.
That it will charge the batteries at FULL amps.
Once the voltage is reached which is 52 volts, or close to it. The amps value will go down.
And this is when the DISCHARGER'S will start to work or kick in.
As you see here, it will not try to discharge the FULL 1.5 amps, but actually the remaining amps which is around less than 1 amp.
And with this value, the discharger's can easily handle this without issues.
Once the amps shown in the converter is like around 0.20 amps or less, this is the time to turn it converter off.
Your battery should be fully charged and at the same time top balanced.
WIRING DIAGRAM
PARTS NEEDED
BOOST CONVERTER
900W CC/CV DC to DC Boost Converter 8-60V to 10-120V 15A Step Up Power Supply.
What is really good about this product is that it will take any voltage as input as long as they are lower than the output voltage. So if you are planning on charging a 24 volt battery, then make sure you make sure that input voltage is a few volts below it. Like in my case, I am using a 19 volts laptop power supply. I am using it for my 24v, 36v, and 48v batteries.
Also, please take note. That every time you have to change the voltage and current settings every time you change your battery system. Example, charging a 48v system, and then later, charging a 24v system.
BALANCER / DISCHARGER
3 in 1 Battery Medic Balancer and Discharger.
What i like about this product is that i see all the voltage all at the same time. This one can handle 6S battery packs. So if you are going to balance/charge a 7S or more, in my case, 14S, then you will need 3 of these devices.
In my case, i divided my 14S batteries into three groups. 5S, 5S, and 4S balance leads.
Also, another thing I like about this product is that, i can now top balance charge them, at different levels. Example, i always now top balance my batteries at 3.90 volts, if i am doing neighborhood rounds. And top balance them at 4.00 volts, when doing longer trips.
Bangood Link - This one is a little better if you can wait for the shipping and pay extra. This one has a bigger load balancer, so it is faster.
Youtube Link (bigger load balancer)
POWER SUPPLY
12-24 volts power supply with enough wattage.
You can use these server power supplies, If you know how to harvest 12 volts from it.
Buy here.,
You can also use laptop power supply.
Currently this is what i use. But not all laptop power supply is the same. You need to look at the total wattage. In my case, i were able to find a Dell 180 watt laptop brick type power supply. This means I can do several configuration depending on the voltage I ran it with.
at 48 volts (13s), I can run it up to 3 amps, or 52 x 3 = 156 watts
at 36 volts (10s), I can run it up to 4 amps, or 41 x 4 = 164 watts
at 24 volts (7s), I can run it up to 6 amps, or 28 x 6 = 168 watts
NOTE: I only charge my li-ion batteries at 4.0 volts max. Normally at 3.90 volts. Also, I always leave room for the wattage and not max the wattage (volts x amps) killing the power supply prematurely.
You can probably find better deal out there. Dell 180 watt link here.
