End-of-life BESS systems

A BESS (battery energy storage system) reaches the end of its useful life when its available energy no longer meets the contract, not when it stops working. EcoBaterías tests decommissioned modules on site, grades them rack by rack and decides between repair, refurbishment, second life and recycling. We coordinate pickup with licensed hazardous-waste carriers, and the authorized receiving facility issues the valorization certificate for EPR reporting.

Thresholds and times: EcoBaterías test protocol, published in lithium battery testing · Recycling price: services (UF is Chile’s inflation-indexed unit of account) · September 26, 2026.

Why do modules arrive before end of life?

Intuition says a storage system is retired when it stops working. In practice the opposite happens: the system keeps running, but its available energy falls below what the contract or the revenue model requires, and an intervention becomes necessary. The modules that reach our laboratory almost always come from one of four situations:

• Warranty claims. A rack falls below the committed degradation curve and the manufacturer or integrator needs an independent failure analysis.
• Capacity upgrades. When a plant is expanded, whole racks are replaced to keep the block homogeneous, and the outgoing racks still hold usable energy.
• Architecture or supplier change. The system is reconfigured and modules are left unused, undamaged and without a destination.
• Incidents. An electrical fault, a thermal event or mechanical damage forces part of the system to be segregated, and it must be graded before it is moved.

In the first three cases the material is not scrap: it is a heterogeneous batch that needs measurement. In the fourth, safety comes first, and grading decides what can be moved and how.

How much storage does Chile have, and what does it imply?

Battery storage is no longer marginal in the Chilean power system. In May 2026 there were 8,786 MWh in operation, according to the National Energy Commission; at the end of June there were also 11,773 MWh in testing and 19,223 MWh under construction, according to the Ministry of Energy. The Commission projects more than 20,000 MWh by the end of 2026; that is a published projection, not installed capacity, and it must be read that way.

For owners still deciding whether to install storage, Carlos Jofré, founder of SolarPro, offers independent battery storage (BESS) strategy advice (opens in a new tab); end of life is best budgeted from that point.

EcoBaterías estimates that, at steady state, that fleet will generate between 240 and 1,540 t a year of modules damaged before operation or replaced under warranty. It is our own scenario-based estimate, not a figure declared by the owners.

What matters for end of life is not the total but its shape: a fleet that grows fast produces, a few years later, a steady flow of modules removed through warranty, expansion and reconfiguration. That flow starts before the first system completes its design life. That design life depends on the chemistry, the cycles and the depth of discharge the system is sized for, as explained in SolarPro Chile’s guide to sizing BESS batteries (opens in a new tab) (in Spanish).

Sources: National Energy Commission, via Reporte Minero (opens in a new tab) (operation and projection for end of 2026) · Ministry of Energy, via pv magazine (opens in a new tab) (testing and construction, 2026-06-30) · in-house estimate of damaged and warranty modules · October 6, 2026.

On-site testing: EIS and grading by rack and module

Moving a full container to find out what is inside is expensive and, with modules of unknown condition, risky. So the work starts at the client’s site, before anything is touched. Impedance spectroscopy (EIS) measures how the module responds to signals of different frequencies and separates the resistance of its connections from the internal degradation of the cells.

1. Document and safety reviewManagement-system logs, alarms, thermal and insulation history are reviewed, and the working perimeter is defined.
2. Electrical measurement per rackOpen-circuit voltage, module-to-module spread, insulation to ground and internal resistance: the first separation between healthy and suspect racks happens here, with no dismantling.
3. Impedance spectroscopy (EIS) per moduleEIS grades modules in minutes and detects degradation that nominal capacity does not reveal. It is the tool that makes grading hundreds of modules in one campaign feasible.
4. Capacity testing on a sampleA representative sample per rack is selected and put through a full charge and discharge cycle to anchor the EIS results to a real energy measurement.
5. Self-discharge and cross-checkVoltage drop at rest over 24 hours is measured on doubtful modules; it is the filter that catches defects you cannot see.
6. Grading and pickup planEvery module is assigned a route and every batch a transport. Only what already has a destination and paperwork is moved.

In a storage plant you do not retire the system: you retire the racks that stopped performing. The difference between the two is the whole recoverable value.

Testing times

We publish what we measure and we do not turn laboratory times into delivery promises per megawatt-hour: real campaign throughput depends on site access, system architecture and the share of modules that need full testing.

Swipe to see the whole table

Source: EcoBaterías test protocol (laboratory times, not a contractual lead-time commitment) · September 26, 2026.

The four routes of a BESS module

Grading always ends in one of these four routes, the same ones we apply to any lithium battery:

Before requesting the test, the owner can run a first comparison of routes with LifetimeBESS second-life forecasting for grid batteries (opens in a new tab); on-site testing then confirms the route of each module.

What are the owner’s obligations?

A decommissioned storage module is handled as hazardous waste unless a characterization shows otherwise. These are the obligations worth settling before pickup starts:

• Handling as hazardous waste. Supreme Decree (DS) 148/2003 on hazardous-waste management requires authorized storage for six months at most, transport under a health permit, a declaration in SIDREP (Chile’s national hazardous-waste declaration and tracking system) and a management plan for anyone generating more than 12 tonnes of hazardous waste a year (or more than 12 kg of acutely toxic waste).
• Class 9 transport. Lithium-ion modules travel as UN 3480: intact modules going to recycling under special provision 377 with packing instruction P909; damaged ones under special provision 376 with P908, or P911 if they could react dangerously. A complete, intact BESS container whose batteries meet UN 38.3 and are secured in racks can travel as UN 3536 (special provision 389), with placards on two opposite sides. We coordinate pickup with licensed hazardous-waste carriers: how collection and transport work.
• Proposed annual declaration (Art. 40). The draft battery decree proposes an annual declaration before May 31 through the RETC single window for industrial consumers and storage installations above 1 MWh.
• Preparation for reuse (Art. 22). The same draft proposes that at least 30% of the lithium-ion target be met through preparation for reuse, which gives regulatory value to grading before recycling.
• Law in force. All of the above rests on Chile’s Extended Producer Responsibility law (Ley REP, Law No. 20,920); the battery targets decree does not exist yet and the ministry’s deadline to propose it is January 29, 2027.

Sources: Law No. 20,920, Library of the National Congress of Chile (opens in a new tab) · DS 148/2003, Articles 25, 31 and 36 (opens in a new tab) · RID 2025, special provisions 376, 377 and 389 (opens in a new tab) · draft battery decree, Ministry of the Environment (Res. Ex. 821/2026) (opens in a new tab) · September 26, 2026.

Coverage and logistics

We do the testing at our facilities or coordinated on site, case by case, and we coordinate pickup with licensed hazardous-waste carriers from any region of Chile. Whatever continues to second life travels to Santiago, where it is prepared; whatever goes to recycling is managed with authorized receiving facilities.

Campaigns are organized in batches: each batch leaves with its file, its code and its transport document, and none is moved before it has been graded. That discipline is what allows the authorized receiving facility to issue a valorization certificate that survives an audit.

What do we deliver?

• Test report per rack and per module, with measured energy, internal resistance, spread and observations.
• Grading by route, with the number of modules in each one and the destination of each batch.
• Valorization certificate from the authorized receiving facility, for whatever enters recycling, to support the producer’s reporting.
• Usable-energy label for modules that continue to stationary second life.

What goes to recycling follows this path: we manage its valorization with authorized receiving facilities, in Chile or in OECD countries where applicable; the authorized receiving facility closes the SIDREP declaration and issues the valorization certificate. Recycling lithium-ion batteries, managed with authorized receiving facilities, costs 22 UF per tonne + VAT; details in lithium battery recycling for companies.

How do you hire the service?

1. BackgroundYou tell us the technology, number of racks, installed MWh, commissioning year and location.
2. Site visit and testingWe review the management-system logs and measure rack by rack.
3. Report and gradingYou receive the result by route, with the destination and the document that applies to each batch.
4. PickupWe coordinate pickup with licensed hazardous-waste carriers and the SIDREP declaration when the module is waste.
5. Close-outValorization certificate from the authorized receiving facility for what is recycled and a usable-energy label for what continues to second life.

The price of testing and pickup and the lead times are confirmed in the quote. We reply within 48 business hours.

Frequently asked questions

Sources