A power-conversion board in an energy-storage system is asked to do two things at once that pull in opposite directions: move a large amount of energy efficiently, and make a precise measurement of what it is doing so the control loop can act on it. The first requirement wants copper and heat; the second wants quiet signals and stable references; both have to share one piece of laminate. This guide covers the boards, battery management, protection, monitoring, testing and materials involved in energy-storage PCBA, and links to a dedicated BMS page for the battery-management board itself.
What Boards Are in an Energy Storage System?
- Inverter and PCS control boards – the power stage, gate drive, DC-link monitoring and protection for grid-tie and hybrid inverters.
- BMS and cell-monitoring boards – the boards that watch cell voltage, temperature and current and keep the pack safe. These are covered in depth on the BMS PCBA page.
- DC-DC converter boards – the stages that move energy between the battery, the bus and the load.
- Grid-tie and communication interface boards – the interfaces that connect the system to the grid and to plant monitoring.
Battery Management and Monitoring
Battery management is where storage systems live or die. The board has to monitor cell voltage, pack current and temperature across the operating range, balance cells, and open the contactor when a limit is exceeded. The measurement side has to be quiet next to the switching side: shunt or sensor placement relative to the gate loop, analogue-ground return separated from power ground, and switching-node distance from measurement traces are layout decisions made at review, because they cannot be corrected at assembly. Monitoring and protection share the same production record, so a question about a specific unit is answered from build data rather than from memory.
Temperature and Current Sensing
Energy-storage boards carry high current and run warm, so sensing accuracy depends on where the sensor sits and how its signal returns are routed. Current is measured with shunts or hall devices placed to avoid the switching node; temperature is measured at the cells, at the power devices and at the busbars. Both are agreed at DFM, and the coating and masking plan keeps sense lines and test points clear.
Protection and Isolation
Storage systems are connected to the grid and to a battery, so the consequence of a marginal joint is not a failed test – it is a field event. Protection covers over-voltage, over-current, over-temperature and insulation monitoring, and the isolation boundary between the control side and the power side is reviewed per programme rather than left to the assembly supplier to interpret. Acceptance runs to IPC-A-610 Class 2 or Class 3 as the product requires, with X-ray on hidden joints and lot-level records.
Communication Interfaces
Most storage boards talk to the rest of the system over CAN, RS-485, Modbus or Ethernet, plus the isolation barriers those links require. The layout review covers signal integrity on those links and the isolation boundary between the communication side and the power side, so a noisy environment does not corrupt the data the controller relies on.
Functional Testing
Kilandu runs the standard two-tier inspection – in-process: SPI + AOI + X-ray on hidden joints, and electrical: ICT + FCT against the agreed test specification. For storage boards the functional test includes the routines the product needs: protection-trip behaviour, insulation and ground-fault monitoring, and contactor and balancing function. The test scope is agreed at quotation and applied through the flow rather than added at the end.
Conformal Coating and Environmental Protection
Inverters and storage systems are installed in garages, plant rooms, roof spaces and outdoor cabinets, so humidity, condensation and airborne contamination are normal rather than exceptional. Conformal coating protects the joints and the surface, but it has to be specified with the same care as the electrical design: a connector that should not be coated, a test point that must stay accessible, a cure method that suits the components already in place. Those details are agreed per programme instead of being applied as a blanket finish.
Materials and the Thermal Path
On a conversion board the electrical path and the thermal path are usually the same copper. Copper weight under a switching device, a thermal via array into an internal plane, an exposed pad or a heatsink on the far side: each element only works if the others are specified with it. Heavy copper inner and outer layers, metal-core constructions where heat must leave the board, and reflow profiles developed for high-mass assemblies are all agreed at review so the board completes rather than merely wets.
Starting an Energy Storage Programme
Send the Gerber files, the bill of materials with manufacturer part numbers, the quantity, the acceptance class and any environmental requirement. Where the programme involves a grid connection or a battery interface, stating the standard the product must meet lets the assembly and inspection plan be set accordingly. The heavy copper boards these stages are usually built on are covered under thick-copper PCB, and the team can be reached at alden@kilandu.com. Typical turnkey lead time is 2 to 5 weeks depending on BOM complexity and component availability.
Power electronics boards in conversion and storage systems
Power conversion and storage equipment is built around a switching stage, and the board carrying it is asked to do three jobs at once: carry current, move heat, and keep the control side electrically quiet. Heavy copper, metal core and thick-plate constructions exist to serve the first two. What decides the third is how the assembly surrounds the switching devices.
What a switching stage asks of the assembly
Gate drive loops, current sense paths and the drain-source or collector-emitter connections are the parts of a power board where layout and assembly meet. Loop inductance is set at layout, but it only holds if the components are placed as designed and the joints are sound, which is why the power devices on these boards are checked by X-ray rather than by visual inspection alone. Where a module or a press-fit device is used instead of a discrete package, it is fitted and tested in the same work order as the board around it.
Isolation, creepage and the control boundary
Conversion equipment separates a high-voltage side from a control and communication side, and the assembly has to preserve that separation. Isolation distances are a design property, but the assembly can compromise them: solder residue, coating applied over a boundary that should stay open, or a connector not fully seated. Where conformal coating is used, the areas that must remain uncoated are masked and inspected, and the boundary between the two sides is a stated part of the work instruction rather than an assumption.
Thermal path from device to heatsink
On a converter the thermal path usually runs device, thermal interface, heatsink or housing, and the assembly owns the middle of that chain. Thermal interface material is specified with a thickness and a coverage, mounting torque is set for the hardware used, and where an insulated pad or a metal-core board is involved the stack-up is fixed before the first lot. A path that is only partly specified moves heat into a bottleneck rather than out of the unit, which is why it is treated as one item at quotation.
Boards in this family
Board types Kilandu assembles in this family. Each linked page covers the application, the manufacturing challenge and the process route, so a like-for-like comparison is possible when specifying a new build.
- Energy storage + BMS control board – the battery-management control board of an energy storage pack: cell monitoring, balancing and protection.
- Photovoltaic energy storage inverter – the control and power board that moves energy between the battery and the inverter, with high-voltage multi-channel input and output.
- Portable energy storage bidirectional inverter system – a board that charges the pack and inverts DC to AC for outdoor, emergency and backup power.
- Inverter motherboard – inverter power and output control with overload and temperature protection.
- Lithium battery test monitoring system – the monitoring and management electronics used when lithium cells are tested.
- Intelligent lithium battery production equipment control system – the controller for multi-specification, small-batch lithium battery production lines.
Energy Storage PCBA Manufacturing Capabilities
Energy storage boards are built around three things: the conversion stage, the monitoring and protection set, and the current and thermal path that keeps both within limits. Kilandu builds energy storage PCBA from prototype through pilot to repeat production on the same lines, so an approved first article and a production run share one process route.
- PCB fabrication — board built to the stackup, copper weight and isolation spacing the design calls for.
- Component sourcing — power devices, magnetics, sensing parts, protection ICs, communication modules and connectors sourced through authorised channels, with long-lead items flagged at quotation.
- SMT and DIP — SMT for the control and sensing side, DIP for power terminals, relays, contactors and larger power parts.
- SPI, AOI and X-ray — solder-paste inspection before reflow, optical inspection after placement and after reflow, and X-ray on selected builds.
- Programming — controller firmware programmed on the board, read back and recorded per unit.
- Box build — supplied as a box build with harness, labels and packaging where the programme requires it.
- Conformal coating — applied to designated areas, with connectors and test points masked.
Prototype lead time is 5 to 8 working days; volume production runs 2 to 5 weeks; repeat orders to an approved build run 2 to 3 weeks.
Energy Storage PCBA Quality Control
Quality control on a storage build is a chain, because each step's record is what makes the next step meaningful. Kilandu runs the chain below on every build, not only on the lots a customer chooses to audit.
- Incoming inspection — components checked against the BOM and the approved-vendor list; reels and trays without a traceable code are not released to the line.
- SPI, AOI and X-ray — in-process inspection as described above.
- IPQC — checks during the build rather than only at the end.
- First Article — inspected and measured against every specified limit, retained as a golden sample, and approved in writing before the volume run is released.
- Traceability — per-lot records from incoming material through placement, soldering, inspection, programming and final test.
- Final inspection — against the approved sample.
Automotive-adjacent programs run under IATF 16949:2016 (IATF No. 0596984), and medical-device programs under ISO 13485:2016 (certificate 35825MDQMS0021R0S). Every certificate number, issuing body, scope and validity date is published on the quality assurance page.
Energy Storage PCBA Case Study
The following describes an energy storage control board Kilandu is capable of building. It is a capability example rather than a named customer project: customer names, product models and order quantities are never published. Project-specific data is available under NDA on request.
- Application — residential and commercial energy storage system.
- Assembly — mixed SMT and through-hole.
- Key functions — cell monitoring, balancing, protection, current and temperature sensing, and communication to the system controller.
- Communication — CAN, RS-485, Modbus or Ethernet as the system requires.
- Testing — AOI, X-ray on selected builds, ICT, functional testing of the monitoring and protection behaviour, and programming read-back.
Challenge. In a storage system the board that matters is the one that keeps measuring correctly over years. A monitoring fault that is acceptable in a lab build becomes a service problem once the pack is installed and the drift is only visible on the pack rather than on the bench.
Manufacturing solution. The measurement chain is reviewed at DFM before the first build, including sense-line routing, analogue-ground return and distance from switching nodes. Protection thresholds are verified at the customer's specified values including trip and recovery. Conformal coating is applied where the enclosure requires it, with connectors and test points masked. Programming is read back and recorded per unit, and per-lot records tie every shipped board back to its material and process data.
Result. First article is inspected and approved in writing before the volume run is released, and the retained sample becomes the reference for repeat orders. Repeat production runs to the same BOM, process parameters and test limits.
Energy Storage PCBA FAQ
What is an energy storage PCBA?
An energy storage PCBA is the assembled control board inside a storage system. It handles cell monitoring and balancing, protection, current and temperature measurement, the thermal path, and communication with the rest of the system.
What types of energy storage PCBAs can Kilandu manufacture?
Kilandu builds energy storage PCBA covering battery management and monitoring, power conversion and control, current and temperature sensing, protection and isolation, and communication. Programs run as mixed SMT and through-hole assemblies from prototype through pilot to repeat production.
Can Kilandu assemble customer-supplied components for energy storage PCBAs?
Yes. Build-to-print is the standard model, so components can be sourced by Kilandu or supplied against the approved-vendor list. Long-lead and allocation-risk parts are flagged at quotation, and nothing is substituted without written approval.
What testing is available for energy storage PCBAs?
Testing covers SPI, AOI, X-ray on selected builds, ICT, functional testing of the monitoring and protection behaviour, current and temperature measurement verification, programming read-back and final inspection.
Can Kilandu provide conformal coating for energy storage PCBAs?
Yes. Conformal coating is applied to designated areas where the board sits in a humid or condensation-prone enclosure, with connectors and test points masked.
What information is required for an energy storage PCBA quotation?
Gerber files, a BOM with manufacturer part numbers, the cell specification and count, the communication protocol and the protection thresholds, sent to alden@kilandu.com. Prototype runs take 5 to 8 working days; typical turnkey lead time is 2 to 5 weeks.