Seplos 280(L) 3.0Y Battery Installation Guide: Hassle-Free Steps for DIY Success

Pre-Install Prep: Gather Your Tools & Parts

Included Key Components

• Cabinet, wheels, epoxy boards (A/B/C), end plates
• 16 battery cells, EVA foam, PC gaskets
• Aluminum busbars, sampling plates, balance board sampling lines
• BMS unit, BMS bracket, copper busbars (YS-4/YS-6/YS-7/YS-8)
• All required screws, nuts, and spring washers
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Essential Tools

• Electric batch, torque wrench, PH1/PH2 cross bits
• 10mm/13mm sleeves, hexagonal H2.5 bit, cable ties

Step 1: Cabinet Assembly & Internal Prep

1. Attach the 4 cabinet wheels using 16 M6*14 Phillips hex screws with spring washers. Tighten to a 10Nm torque for a secure fit.
2. Peel the adhesive film off the epoxy boards (A/B/C) and stick them to their designated internal cabinet positions as shown in Figure 2 of the manual.
3. Prep the battery cell surfaces: Apply EVA foam and PC gaskets to the cell faces to prevent friction and short circuits.

Step 2: Battery Cell Stacking & Securing

1. Test your battery cells first—ensure voltage difference is within 0.010V and internal resistance difference is under 0.15mΩ.
2. Stack the 16 cells in series and slide them into the cabinet. Use epoxy board B to separate the two cell columns.
3. Attach the end plate with 6 M8*20 Phillips hex screws. Tighten to a 15Nm torque.
4. If there’s any looseness (common due to minor cell tolerances), add extra foam at the cell heads and tails.

Step 3: Install Aluminum Busbars & Sampling Plates

1. Mount the SF-N1 and SF-N13 aluminum busbars onto the battery cell poles (follow Figure 1 in the manual for placement).
2. Stick EVA foam onto the battens and align the holes perfectly.
3. Secure the sampling plates to the battens with 6 M4*8 Phillips hex screws each. Tighten to a 3Nm torque—don’t over-tighten!

Step 4: Balance Board & Sampling Wiring Setup

1. Install the pressure strip beads, distinguishing between A/B boards. Use 8 M5*8 Phillips hex screws and tighten to 5Nm.
2. Insert the sampling wire lugs into their corresponding cell poles.
3. Connect the balance board sampling lines, then lock the aluminum busbars in place with 30 M6 flange nuts (6Nm torque).
4. Use cable ties to bundle the sampling lines neatly—this prevents tangling and damage later.

Step 5: BMS Mounting & Core Connections

1. Fasten the BMS to its sheet metal bracket with 6 M3*8 Phillips round head screws (1Nm torque).
2. Install the YS-6 and YS-8 copper busbars using the BMS-provided screws (8Nm torque for a solid connection).
3. Attach the small B+ line to the BMS (1Nm torque) and plug in the black/white sampling lines and LCD display line.

Step 6: Front Panel & Balance Board Finalization

1. Stick a thermal pad onto the balance board to ensure heat dissipation.
2. Install the balance board and adapter plate with 3 M3*8 Phillips screws (1Nm torque). Add the terminal sockets, switch key, and fuse holder per the manual’s Figure 2.
3. Solder the switch key plug and fasten it to the ON/OFF position. Secure the YS-4/YS-7 copper busbars and fuses (8Nm torque).
4. Plug in the adapter board data cables to complete this section.

Step 7: Chassis Integration & Final Wiring

1. Mount the BMS bracket into the cabinet with 4 M5*14 Phillips hex screws (5Nm torque).
2. Attach the cabinet roof using M4*10 hex socket countersunk screws (3Nm torque).
3. Plug the balance board sampling line and switch line into the BMS. Install the B+ and B- copper busbars, securing them with M6 flange nuts (6Nm torque).
4. Lock the P- YS-8 copper busbar with an M8*16 Phillips hex screw (15Nm torque).

Step 8: Close the Cabinet & Complete Capacity Learning

1. Install the LCD display and LED light panel on the cabinet cover with M3*8 Phillips round head screws (1Nm torque). Plug in their respective cables.
2. Close the cabinet cover and tighten 17 M4*10 hex socket countersunk screws (3Nm torque). Stick the PVC sticker for a finished look.
3. Critical Final Step: Capacity Learning
4. Fully charge the battery with a 100A current.
5. Trigger the battery system protection mode (100A current recommended).
6. Recharge the battery to 50% capacity (100A current) to finish the learning process.

Pro Tips for a Smooth Installation

• Always follow the torque specs: Too tight can crack parts; too loose causes safety risks.
• Label wires before disconnecting (if you need to adjust anything) to avoid mix-ups.
• If you encounter loose gaps, don’t hesitate to add extra foam—better safe than sorry.
  

Wrap Up