PV Magazine Webinar – Alleviating Battery Storage Growing Pains Through Quality Assurance

On June 30, together with Fluence, we had a PV Magazine webinar discussion on battery energy storage system regarding its current maturity of development, main quality and safety concerns, and STS and Fluence’ practices in mitigating these concerns.

We also prepared a key-points summary of STS’ sharing for you as below:

– Newcomers in the BESS industry – Quality requires an investment from manufacturers and installers

The level of maturity of the BESS industry today is lower than the one of the solar industry, and that has a lot of consequences regarding quality.

Contrary to the PV industry today where most players show ability to deliver the right level of quality (IQC, IPQC, FQC, SOPs, etc.), we observe in BESS inspections some basic quality issues (wrong cabling, damaged components installed, and cell and module sorting issues, etc.).

As an illustrative example, we have captured some lots with more than 90% defective systems during witness of Factory Acceptance Test. Before we were hired, the client used to receive these defective systems and was taking on them the burden of repairing them on site.

Besides, some manufacturers are not able to deliver on time because, for instance, the manpower ramp-up and training of operators was not well budgeted in the original planning. Expediting services can help capture this issue long in advance and prevent shipping delays.

This observation is also true for the level of maturity of installers. It is hard today to find adequate manpower and it is time-consuming to train local manpower.

Recommended quality assurance practices:

– Multiple-dimensional Supplier Evaluation: manufacturing process audit, product design and development audit, supply chain assessment are amongst the most popular dimensions to evaluate a supplier.

– Standard Operating Procedures and Factory Acceptance Test Procedures review before production can avoid surprising discoveries or inadequacy during FAT.

-Production Supervision (IQC, IPQC, FQC) or Verification of Manufacturing Records can improve significantly the quality of the systems delivered.

-New Product Challenges – From safety features to factory acceptance tests

As surprising as it may seem, there is no standard today for the capacity test of a battery energy storage system. Testing procedure may vary from one manufacturer to another. We have seen manufacturers changing the procedure during factory acceptance tests to “pass”, and copy-pasting the capacity test results from one container to another, because it takes a long time to charge/discharge.

Product safety is another concern of paramount importance. There have been several very large safety recalls already in this industry. We surprisingly also find safety-related issues during factory acceptance test (e.g. fire protection test failure, temperature sensor failure, water tightness failure, etc.). It is also a risk that the shipping methods are not yet standardized; every manufacturer may have a different shipping method.

– New Market Drivers Impacting Quality

We see that the quality control steps down after the supply chain bifurcation between automotive and stationary applications. Besides, the competition for battery supply is expected to be fierce between these two applications in the future.

Similar to PV industry, supply chains are also challenging today for BESS. Many things are expected to be in scarce supply, including materials and production facilities. Besides, some systems are today only at the level of prototypes (with ramp-up of production planned during delivery of the project), which may carry a high risk of delayed delivery. We see that expediting (asking for the detail project planning of the manufacturer and carrying out a very detail follow-up of this planning) is very valuable to mitigate the delay risk.

Our recommended quality assurance practices for BESS are:

– 100% Factory Acceptance Test witness

– Factory Acceptance Test Procedures review before production

– Container Loading Supervision

– Production Supervision (IQC, IPQC, FQC) or Verification of Manufacturing Records