Repair Bosch 18V 2.0Ah Lithium Battery – Full Cell Replacement & Upgrade to 3.4Ah

Lithium-ion batteries used in power tools can fail due to cell degradation, corrosion, or deep discharge. In this project, we repair a completely dead Bosch 18V 2.0Ah battery and upgrade its capacity to 3.4Ah.

Bosch 18V 2.0Ah Battery Replacement

Initial Symptoms

1. The battery shows no response when the battery level button is pressed. No LEDs turn on, indicating a possible internal failure.
   
   

   

   Battery level indicator shows no light when pressed.

   
   
2. When connected to the charger, the green LED remains static and does not blink. This usually means the charger cannot detect the battery pack.
   
   

   

   Battery connected to charger with static green light.

   
   
3. Voltage reading = 0V.
   
   

   

   Multimeter probes on the main battery terminals..

   
   

This indicates full battery pack failure.

Disassembly Process

1. Remove 8 screws from the battery housing.
   

   

   Removing the 8 screws from the battery housing.

2. Pry open top cover carefully.
   

   

   Prying open the top battery cover.

   
   

3. Remove battery level cover (2 screws).
   
   

   

   Battery level indicator cover.

4. Remove left and right side panels.
   
   

   

   Side covers removed.

   
   

Troubleshooting

1. Remove insulation tape, nickel strips and PCB.
   
   

   

   Insulation tape and nickel strip removed from battery pack.

   
   
2. Inspection revealed the battery cells show heavy corrosion and leakage, which explains the failure.
   
   

   

   Severely corroded and leaked battery cells.

   
   
3. Each cell is tested individually using a multimeter. All cells show 0V, confirming full cell failure.
   
   

   

   Checking voltage on individual 18650 cells.

   
   

Battery Replacement

1. Old cells were removed from the compartment (required gentle hammer tapping).
   
   

   

   Removing stuck battery cells from the compartment.

   
   
2. New NCR18650B 3400mAh lithium-ion cells are installed. This upgrades the battery from 2.0Ah to 3.4Ah capacity.
   
   

   

   New NCR18650B 3400mAh cells installed.

   
   

PCB Repair

1. Battery leakage caused corrosion on the PCB.
   
   

   

   Corrosion on the PCB.

   
   
2. The board is cleaned using isopropyl alcohol, and solder joints are reheated to restore connections.
   
   

   

   Solder joints are reheated to restore connections.

   
   

Reassembly

1. After cleaning and inspection, the PCB is reinstalled carefully into its original position.
   
   

   

   PCB installed back into battery housing.

   
   
2. New nickel strips are cut to match the original dimensions.
   
   

   

   Nickel strip cut to original length.

   
   
3. The nickel strips are spot-welded in the same configuration as the original battery pack.
   
   

   

   Spot welding nickel strips to new cells.

   
   
4. Insulation tape is reapplied to prevent short circuits and improve safety.
   
   

   

   Battery pack insulated with protective tape.

   
   
5. All covers are installed back in reverse order, and screws are tightened securely.
   
   

   

   Battery housing reassembled and secured

   
   

Final Testing

✅ Test 1 – Battery Indicator

Battery level indicator working normally.

✔ Battery level indicator lights up correctly when the button is pressed.
✔ Confirms PCB and indicator circuit are functioning properly.

✅ Test 2 – Charging Test

Battery charging with blinking green LED.

✔ Battery detected by the charger.
✔ Charger green LED blinking, indicating normal charging process.

✅ Test 3 – Load Test

Bosch blower powered by the repaired battery.

✔ Battery tested under load using a Bosch blower.
✔ Tool runs smoothly without power drop.
✔ Runtime is noticeably longer compared to the original 2.0Ah battery.

📦 Where to Buy

Shopee:

1. NCR18650B Battery
2. Spot Welder
3. Nickel Strip

Lazada:

1. NCR18650B Battery

TikTok:

1. NCR18650B Battery
2. Spot Welder
3. Nickel Strip

Aliexpress:

1. NCR18650B Battery
2. Spot Welder
3. Nickel Strip

Conclusion

This repair successfully restored a dead Bosch 18V battery and improved its performance with higher capacity cells. Battery rebuilding can extend tool life and reduce replacement cost — but must be done carefully due to lithium battery risks.

Build a Wind-Powered Jeep (DIY STEM Project) — Step-by-Step Guide

Wind-powered vehicles are a fun way to learn how wind energy can be converted into mechanical motion. In this project, we build a simple wind-powered jeep model using a wooden kit, a motor, wheels, and a propeller. It’s a great hands-on activity for students, classrooms, science fairs, or anyone who enjoys DIY STEM builds.

Wind-Powered Jeep

Parts Included in the Kit

Before starting, lay everything out on a table and check the kit contents:

Insert Board No. 2 into Board No. 1 to form one side frame.

• Wooden boards No. 1 to No. 7 (stacked together in a sheet)

• 4 wheels

• 2 metal axles

• DC motor

• Battery box

• Propeller (fan blade)

• Screws and accessories

• Double-sided tape

✅ Tip: Carefully push out all wooden boards (1–7) from the stack first. This makes the assembly faster and prevents cracking while building.

Step-by-Step Assembly Instructions

Step 1 — Build the First & Second Side Frame

Insert Board No. 2 into Board No. 1 to form one side frame.

Connect Board 2 into Board 1.

Step 3 — Attach Side Frames to the Base

Attach the assembled Boards No. 1 and No. 2 onto Board No. 3 (the base board).

Lock the side frames onto Board 3.

Step 4 — Battery Box + Rear Supports

• Thread the battery box wires through the small holes in Board No. 3.
  
  

  

  Pass the wires through the holes neatly.

• Attach Boards No. 4 and No. 5 to the rear of Board No. 3.
  
  

  

  Build the rear support frame.

• Fix the battery box in place using double-sided tape.
  
  

  

  Tape the battery box so it won’t move.

  
  

Step 5 — Add Board 6 + Connect Wires

• Attach Board No. 6 onto Boards No. 4 and No. 5.
  
  

  

  Lock the top board into the rear frame.

• Connect the motor wires:
  

  

  Black wire goes to the right motor terminal.

• Black wire → right side of the motor.

• Red wire → left side of the motor.

Step 6 — Motor, Propeller, and Axles

• Insert the two metal axles through the holes in Board No. 1.
  

  

  Slide axles through to prepare for wheels.

• Attach the motor to the rear of Board No. 3.
  

• Insert the propeller onto the motor shaft.
  

  

  Push the propeller onto the motor shaft.

• Use double-sided tape to secure the motor firmly (so it doesn’t shift while running).
  

  

  Tape the motor to keep it stable.

  
  

Step 7 — Wheels + Final Check

• Install the four wheels onto the metal axles.
  

  

  Push wheels onto each axle end.

• Check that everything is straight and tight.
  

  

  Check all parts are tight and aligned.

✅ Assembly complete!

Power Up the Jeep

Now for the fun part:

1. Insert 2×AA batteries into the battery box.
   

   

   Slide down the knife switch to turn it ON.

2. Your jeep is now ready to run!

📦 Where to Buy

Shopee:

1. Wind Jeep

Lazada:

1. Wind Jeep

TikTok:

1. Wind Jeep

Aliexpress:

1. Wind Jeep

Final Thoughts

This wind-powered jeep is a simple but powerful way to explore STEM concepts through building. Once you finish, try testing it with different wind sources—like a fan at different speeds—and observe how the motion changes.

If you enjoyed this project, consider making more builds like rubber-band cars, solar cars, or balloon-powered racers.