Hey! everyone My name is Steve .

Today i'm going to show you How to make a 3S 18650 Battery Pack

3S batteries are widely used in many application such as Bluetooth Speaker , Rc Cars & and many things you can think of .

it can easily power any 12v application with no issues

Let's Get Started

Click Here to See The Video

Step 1: Features

Supply Output

  • Nominal voltage - 11.1 v
  • Maximum voltage - 12.6 v
  • low voltage - 9 v

Safety Features

  • Over-Discharge Protection
  • Over-Charge Protection
  • Short-Circuit Protection

Step 2: Stuff I Used

  • 18650 Battery " i've salvage this battery from a laptop battery Click here to see how "
  • 18650 Battery Holder
  • 10 A BMS Board

Buying Links



Step 3: The Things You Need to Know

• It is necessary to use same capacity battery little up and down will be be ok ( example - 1750 mah , 1740 mah , 1730 mah )
• If you want to know how to check your real battery capacity "Click Here to See The Video "
• And it is very necessary to keep all the battery at same voltage " I found a best way to do this by connecting all the batteries in parallel and leave it over night "
• Be careful while doing this don't reverse the polarity

Step 4: Attaching the BMS & Battery Holder

  • Put 3 battery on the 18650 Battery Holder
  • Use a double sided tape to stick BMS on the batteries

Step 5: Connection

  • Connect all the battery as shown in the schematic

Step 6: How to Charge Them

  • you can just use a 12.6 v lithium battery charger to charge this battery
  • By the way i'll make a lithium battery charger later on so stay tuned for that

Step 7: Finishing

  • Now check the output voltage

Click Here to See The Video

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Hi Steve,<br><br>How long with this 12V last playing on a Bluetooth speaker?
<p>Do you know if I can put cells in parallel to make a 3S2P battery pack?</p>
yeah no issues with that
<p>A Li-Ion battery like a 18650 has a &quot;nominal&quot; voltage of 3.7Volts, (and ewen then there are 2 cell's connected in serious, thus ewery individual cell producing a voltage over a potentional of appr. 1.85Volt/cell). Still, to &quot;recharge&quot; a battery, it requires a higher potential of voltage to be done, You can't just &quot;take&quot; some You allso need to &quot;give&quot; some</p><p>Your picture shows with the multimeter some 12.4Volt. Right? You'we just recharged them batterys.... but just wait for an 2 minutes and do the measurement again.... TaDaa,,,, it want read ower 12V again... Hmmmmmmm..</p>
<p>Don't bilieve this explained above</p>
<p>INPUT/OUTPUT?</p><p>Where is the input = recharge? Where is the output = charge? You got me lost there?</p>

About This Instructable




Bio: Hi my name is Steve and i'm a Creative and I got Technical skills i can build anything just stick to my account . I ... More »
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