Citroën Berlingo Battery Upgrade Guide: 75Ah to CATL 137Ah Lithium Cells

Citroën Berlingo Battery Upgrade Guide: 75Ah to CATL 137Ah Lithium Cells

🔋 A High-Capacity Battery Replacement Solution for Citroën Berlingo Electric

As early electric vehicles continue to age, battery degradation is becoming one of the biggest challenges for owners of the Citroën Berlingo Electric.

Reduced driving range, increasing cell imbalance, and declining usable capacity can make an otherwise reliable electric van much less practical.

For the earlier-generation Citroën Berlingo Electric, replacing the complete vehicle is not always necessary.

A properly engineered high-capacity battery cell upgrade can potentially restore the vehicle while significantly increasing its available battery capacity.

At Cowon Technology, we are developing a replacement solution based on CATL 137Ah prismatic lithium-ion cells, providing a modern alternative to the original 75Ah battery cells.

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🚗 Original Citroën Berlingo Electric Battery

The earlier Citroën Berlingo Electric uses a 22.5kWh lithium-ion traction battery mounted underneath the vehicle floor.

The original battery configuration includes:

• 80 lithium-ion cells
• 3.75V per cell
• 75Ah nominal capacity
• Approximately 22.5kWh total battery capacity

This design allowed the battery pack to remain underneath the cargo floor without significantly reducing the van's usable cargo space.

However, after many years of operation, the original cells may begin to show:

• ❌ Reduced usable capacity
• ❌ Shorter driving range
• ❌ Increased cell voltage difference
• ❌ Faster voltage drop under load
• ❌ Reduced overall battery performance

For vehicles that are still mechanically sound, upgrading the battery can therefore be an attractive alternative to replacing the entire vehicle.

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🔄 Our Upgrade Solution: CATL 137Ah Prismatic Cell

For this project, we are evaluating a CATL 137Ah aluminum-case lithium cell as the replacement battery solution.

CATL 137Ah Cell

Compared with the original 75Ah cells, the new 137Ah solution provides approximately:

137Ah ÷ 75Ah = 1.83

That means the cell-level capacity is approximately 83% higher than the original battery.

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📊 Original 75Ah vs CATL 137Ah

The difference becomes clearer when comparing the two solutions directly.

*Dimensions commonly reported for the original LEV75-type cell body. Terminal height and mounting structure must also be considered during replacement design.

One important advantage of the CATL 137Ah cell is its compact footprint.

Compared with the commonly reported dimensions of the original cell, the CATL cell is:

• Approximately 23 mm shorter
• Approximately 5 mm narrower
• Similar in overall cell-body height

This gives engineers additional space for designing insulation, brackets, busbars and mechanical supports.

However, terminal position and pack-cover clearance must still be verified before final assembly.

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⚡ Potential Battery Capacity Increase

The original Berlingo Electric battery is approximately 22.5kWh.

If an electrically compatible 3.7V-class CATL 137Ah cell is used while retaining an approximately 80-series architecture, the theoretical nominal battery energy could approach:

80 × 3.7V × 137Ah ≈ 40.5kWh

This would represent a substantial increase compared with the original 22.5kWh battery.

Potential Benefits

• 🔋 Much higher battery capacity
• 🚐 Longer driving range
• ⚡ Reduced depth of discharge during daily operation
• 🔄 More usable energy for commercial applications
• 📈 Extended practical service life of the vehicle

Actual usable capacity and driving range will depend on the final cell voltage specification, BMS settings, SOC operating window, vehicle condition, driving speed, payload, temperature and other factors.

Therefore, the upgrade should not simply be considered an “80-cell swap.”

It is a complete battery system integration project.

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⚠️ Battery Upgrade Is More Than Replacing the Cells

A high-capacity EV battery replacement requires several technical factors to be considered.

1️⃣ Mechanical Compatibility

Even when the replacement cell is smaller, the following dimensions must be carefully checked:

• Cell height
• Terminal height
• Terminal position
• Busbar spacing
• Original battery tray structure
• Pack cover clearance
• Cell compression and fixation

The CATL 137Ah cell measures:

148 × 52 × 115 mm

Its shorter length and narrower width provide useful installation flexibility, but custom brackets, spacers or busbars may still be required.

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2️⃣ BMS & CAN Communication

This is one of the most important parts of a capacity upgrade.

The vehicle's original battery management system was designed around the original battery capacity.

When significantly larger cells are installed, the system must still correctly manage:

• SOC calculation
• Cell voltage monitoring
• Charge limits
• Discharge limits
• Regenerative braking
• Temperature monitoring
• Vehicle CAN communication

Capacity upgrades on older Berlingo systems have been reported to require additional work around SOC and CAN data because the vehicle electronics may continue calculating battery status according to the original battery configuration.

Therefore, BMS compatibility must be verified before the battery upgrade is considered complete.

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3️⃣ Busbar and Terminal Design

The replacement cell does not necessarily use the same terminal position or connection structure as the original battery.

A reliable replacement solution may require:

• Customized copper or aluminum busbars
• Proper terminal hardware
• Insulation covers
• Voltage sensing connections
• Temperature sensor placement

Poorly designed busbars can increase electrical resistance and temperature under high load.

This is why mechanical and electrical design must be considered together.

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4️⃣ Cell Matching & Consistency

For an EV battery pack, nominal capacity alone is not enough.

All cells should have closely matched:

• Capacity
• Voltage
• Internal resistance
• Self-discharge characteristics

Before assembly, the cells should be tested and grouped to maintain consistent performance throughout the complete battery pack.

At Cowon, battery cells for replacement projects can be checked for:

✅ Capacity consistency
✅ Voltage consistency
✅ Internal resistance
✅ Appearance and terminal condition
✅ Batch consistency

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🛠️ Typical Citroën Berlingo Battery Upgrade Process

For professional battery replacement projects, we recommend the following workflow:

1. Confirm vehicle generation and original battery configuration
2. Inspect the original battery pack and cell dimensions
3. Confirm available installation space
4. Select the replacement cell
5. Verify voltage and BMS compatibility
6. Design brackets, insulation and busbars
7. Match and test all battery cells
8. Assemble the battery pack
9. Check BMS / CAN communication
10. Perform charging and discharge testing
11. Complete vehicle installation and road testing

This process greatly reduces the risk of compatibility problems after installation.

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🔍 Why Use a 137Ah Cell Instead of Another 75Ah Replacement?

Replacing an old 75Ah battery with another similar-capacity cell can restore the vehicle, but it does not take full advantage of improvements in modern battery technology.

Using a higher-capacity cell provides a different opportunity:

For customers who only want to repair the vehicle at minimum cost, a standard-capacity replacement may be sufficient.

For customers who want to extend both vehicle life and practical driving range, the 137Ah upgrade is much more interesting.

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🚐 Who Is This Solution For?

The CATL 137Ah upgrade is particularly suitable for:

• Citroën Berlingo Electric owners
• EV repair workshops
• Battery rebuilding companies
• Commercial van fleets
• EV conversion specialists
• Companies restoring older electric vehicles

Because every vehicle and battery pack may have different conditions, final compatibility should always be confirmed before ordering.

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💡 What Information Do We Need?

If you are planning a Citroën Berlingo battery replacement or capacity upgrade, please send us:

• Vehicle year
• Exact model
• Original battery capacity
• Original cell model, if available
• Photos of the original battery cell
• Cell dimensions
• Required quantity
• Country / delivery destination

If the battery pack has already been opened, photos of the cell arrangement, terminals and busbars are especially useful.

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🚀 Conclusion

The original Citroën Berlingo Electric was designed around an approximately 22.5kWh / 75Ah battery system.

As these vehicles age, battery degradation does not necessarily mean the vehicle has reached the end of its useful life.

Modern high-capacity lithium cells provide a new upgrade path.

The CATL 137Ah prismatic aluminum cell, measuring only 148 × 52 × 115 mm, offers significantly more capacity while maintaining a compact form factor.

The potential advantages include:

✅ Approx. 83% higher Ah capacity than the original 75Ah cell
✅ Potential for a much larger traction battery
✅ Longer practical driving range
✅ Compact prismatic design
✅ Suitable for customized EV battery rebuilding projects

However, a successful upgrade depends on more than the battery cell itself.

Mechanical fit, terminal design, BMS compatibility, CAN communication, cell consistency and pack testing must all be considered as one complete system.

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🏭 About Cowon Technology

At Cowon Technology, we provide battery solutions for EV replacement and customized battery projects, including:

• EV battery cells
• High-capacity prismatic lithium cells
• Replacement battery solutions
• Customized busbars and connection parts
• Cell matching and testing
• Customized battery pack development

Our goal is not simply to supply battery cells.

We help customers find a practical battery solution based on the vehicle, available installation space and electrical requirements.

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📩 Get a Citroën Berlingo Battery Upgrade Solution

Looking for a replacement battery solution for your Citroën Berlingo Electric?

Send us your:

Vehicle model + year + original cell photos + required quantity

and our team can help evaluate the suitable battery cell and upgrade configuration.