Key Takeaways
- EV fleets face a fundamentally different battery service challenge than ICE fleets — high-voltage packs require specialized equipment, trained technicians, and a defined service strategy before failures occur.
- The four primary EV pack service scenarios — depowering, module balancing, rescue charging, and pack-level diagnostics — require different tools and different skill sets.
- Deciding between in-house service, dealer service, and OEM return programs should happen before the first EV joins the fleet, not after the first breakdown.
- The 12V auxiliary battery in fleet EVs still requires the same PM testing protocol as conventional vehicles — and still fails on a conventional timeline.
- Midtronics provides EV fleet service tools that cover all four service scenarios, with data connectivity for fleet-level tracking.
Electrification is taking the Heavy Duty Industry by storm. Most companies are either in the process of ordering and implementing an EV Fleet, or are planning the start of an EV Fleet. Further, most Fleets and OEM’s are focusing the majority of their resources and bandwidth on vehicle specification, on-road functionality, battery range, etc. Indeed, these are all pressing and important considerations.
OK, fast forward just a bit. Once the trucks are at dealerships ready for sale, on the road and operational, or in need of some battery service – What is the service plan on how to manage battery issues? Since the battery is the key component to truck EV propulsion systems, it makes sense to start thinking now about how to manage battery issues that will present themselves to Fleet Maintenance organizations.
These are the type of Battery Applications that will require attention:
- Pack Removal – The beginning stages of a Fleet Service Strategy will likely start with removing faulty battery packs from the vehicle and sending them to an authorized service center for them to diagnose & repair or replace the pack.
- To remove the pack lid and work inside of a battery pack it is recommended to reduce the pack voltage by discharging to a lower State of Charge (SoC) prior to disassembly.
- Transportation – It is recommended practice that when transporting any battery pack the power should be reduced to 30% SoC prior to transport. This would apply to transporting packs between Fleet central maintenance facilities where spare packs may be inventoried to local service shops; or transporting a faulty pack to a designated OEM service center. Regardless, you’ll want to reduce pack power to 30% SoC to be assured safe transport.
- Crash Discharge – When accidents happen, and they will, the objective is to safely neutralize any risk from damage to the battery by depowering it to 0% SoC as quickly as the circumstances permit. Some companies already have designated containment areas for crash vehicles to address the risks of battery volatility.
- Module Level Service – As EV truck volume grows, Fleet Maintenance team, dealerships and authorized service providers will most certainly evolve to pack level service because Pack Swapping will become cost prohibitive. Generally, maintenance teams performing pack level service will be replacing modules within the pack that can no longer meet specification.
- When installing a replacement module into a pack, it is essential to balance the State of Charge of the new module with the existing modules. Accurate balancing ensures full performance from the serviced pack.
Just as Truck Electrification adoption is part of everyone’s strategic planning today, processes and equipment to service the battery packs and maintain Fleet uptime and operational efficiency must be a focal point as well. The imperative when working with High Voltage Battery Systems is choosing discharging and module balancing tools that that are 1) Safe to users and vehicles and 2) Cost Effective and Easy to Use.
Trust Midtronics to help you build your EV battery service strategy. Find more information about our HD Fleet solutions.
Frequently Asked Questions
What makes EV battery service different from conventional fleet battery maintenance?
ICE fleet battery maintenance centers on the 12V starting battery — a well-understood, standardized service. EV fleet battery service adds high-voltage pack diagnostics, module-level service, and safety-critical depowering procedures that require specialized equipment and HV-certified technicians. The 12V battery still exists and still needs conventional PM testing, but it’s no longer the only battery system that matters.
What are the main EV battery service scenarios fleet operators need to plan for?
Four core scenarios: (1) Pack depowering — safely removing energy from the HV pack for collision handling or pack shipping. (2) Module diagnostics and replacement — identifying and replacing failed cells or modules within the pack. (3) Module balancing — equalizing state-of-charge across modules after replacement. (4) Rescue charging — bringing a depleted HV battery up to a state of charge sufficient to crank the engine. Each requires different equipment.
Should an EV fleet service high-voltage batteries in-house or outsource?
That depends on fleet size, EV volume, and technician training capacity. High-volume EV fleets benefit significantly from in-house capability — faster turnaround, lower per-event cost, and no dependence on dealer availability. Smaller fleets may find that a dealer service arrangement or OEM return program is more cost-effective until EV volume justifies the tool investment and training. Midtronics’ EV Solutions team can help evaluate the right approach.
Do EV fleet vehicles still need conventional 12V battery testing?
Yes. Every EV — regardless of the high-voltage architecture — relies on a 12V auxiliary battery to power electronics and wake up the HV system. That 12V battery degrades on a conventional timeline and will fail without proper PM testing. The xLVS-9000 is built specifically for 12V diagnostics in EV applications, and should be part of every fleet’s EV PM protocol.
What tools does Midtronics offer for EV fleet battery service?
Midtronics covers all four service scenarios: the xPD-1K for pack depowering, the xMB-9640 for module balancing, the xRC-3363 for rescue charging, and the xHVS-3000 for pack-level diagnostics. BMIS integration enables fleet-wide data tracking across all service events.
What safety certifications do technicians need for EV fleet battery service?
HV-certified technicians are required for any work on live high-voltage components. I-CAR’s EV curriculum and OEM-specific training programs are the primary certification paths. OSHA electrical safety standards also apply to high-voltage vehicle service environments. Fleet operators should verify technician certification before authorizing any hands-on HV work.