Understanding the Total Sustainability Impact of Li-ion UPS Batteries

Overview

The paper judges battery choice over four lifecycle phases rather than operating life and price alone: raw-material mining, manufacturing, operation, and end-of-life repurposing or recycling. The comparison is between lithium-ion and valve-regulated lead-acid (VRLA). Best practices and vendor attributes are listed for each phase, so a reader finds items that can be carried straight into a purchasing specification. Each phase is treated separately, so a weakness in one phase is not hidden by strength in another.

The conclusion is that, on balance, Li-ion has the lower lifecycle impact today. In the quantitative comparison Li-ion scores lower on most of nine environmental metrics. Two reasons stand out: smaller mass and fewer replacements. For comparable runtime in the example UPS, VRLA batteries weigh about 11,340 kg (25,000 lb) against about 2,767 kg (6,100 lb) for Li-ion. VRLA is typically replaced about twice over a 10-year UPS life, whereas Li-ion often lasts the whole UPS life.

The paper is candid about its limit, which is end of life. Lead-acid batteries have about a 99.3% return-for-recycling rate in the US, while the Li-ion recycling chain is less mature. Li-ion's advantage therefore rests on mining, manufacturing and operation gains outweighing an uncertain end of life. The balance should be revisited as recycling infrastructure matures, and replacement count remains as decisive as mass in both the waste and the cost calculation.

Key points

1. Example UPS battery mass for comparable runtime: VRLA about 11,340 kg (25,000 lb), Li-ion about 2,767 kg (6,100 lb).
2. VRLA is typically replaced about 2 times over a 10-year UPS life.
3. Li-ion often lasts the whole UPS life.
4. Lead-acid batteries have about a 99.3% return-for-recycling rate in the US.
5. Li-ion shows lower impact on most of nine environmental metrics in the quantitative comparison.
6. Four lifecycle phases are covered: mining, manufacturing, operation, end of life.
7. The Li-ion recycling chain is less mature than lead-acid's.

Using it in design

• Give the battery catalog these fields: chemistry, mass per kWh, design life, replacements over UPS life and recycling rate.
• Use battery mass in the structural floor-load check: roughly four times the weight for VRLA at the same runtime can drive slab capacity.
• Default replacements to 2 per 10 years for VRLA and 0 for Li-ion, and carry them into TCO and embodied-carbon calculations.
• Use the per-phase best practices as a checklist in the supplier specification.

Who should read it

Design engineers selecting UPS batteries and decision makers who need a total-cost and sustainability comparison.

Related standards

• IEC 62040-3
• IEC 62619
• UL 9540A
• NFPA 855

Publication details

Authors

Raymond Lizotte; Wendy Torell

Publisher

Schneider Electric

Year

2021

Document number

WP 71

Document language

English

Source type

Manufacturer

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation