What is an AACE Class 3 cost estimate?

AACE International defines five classes of cost estimate, Class 5 through Class 1, ranked by how much engineering definition backs the number and how tight the expected accuracy range is. Class 5 is a rough order-of-magnitude estimate made with minimal process detail. Class 1 is a definitive estimate built from complete engineering, used for final investment decisions. Class 3 sits in the middle: enough process and mass-and-energy-balance detail to support a budget-authorization or capex-screening decision, typically accurate to within roughly -20% to +30% of the eventual cost. It's the class of estimate a gigafactory pre-FID decision or a supplier negotiation typically needs — detailed enough to defend to a board, without requiring a complete engineering design first.

What does mass and energy balance closure mean in a cell cost model?

It means every material and energy input to the cell manufacturing process is accounted for and reconciled — the mass of active material, electrolyte, and packaging going in matches the mass of the finished cell plus process losses, and the energy consumed across each process step is tracked and totaled. A cost model without balance closure can silently double-count or drop material flows, which understates or overstates the true cost. Closure is what makes the resulting per-kWh number defensible rather than a rough guess dressed up as a spreadsheet.

Which cell chemistries does the TEA model support?

The current demo model runs NMC-811 on the public BatPaC 5.2 reference basis. LFP, NMC-622, NCA, and custom chemistry inputs are on the near-term roadmap. Bring your chemistry to a demo call and we'll show what the cost stack looks like for your specific BOM.

How is live materials pricing joined to the cost model?

Wensura's time-series materials pricing corpus is joined directly to the cell BOM inputs of the TEA engine. When a tracked commodity — cobalt, nickel, lithium — moves, the cathode and related cost-stack segments recompute against the new price, and the per-kWh total and cost waterfall rebuild in seconds, without a manual spreadsheet rebuild.

Techno-Economic Analysis

AACE Class 3 cost modeling
for battery cells.

A cell BOM cost estimate is only as trustworthy as the methodology behind it. Here's what AACE Class 3 means, why mass & energy balance closure matters, and how Wensura joins live materials pricing to the model.

The Basics

What "techno-economic analysis" actually means here.

Techno-economic analysis (TEA) is the practice of costing out a manufacturing process from its underlying engineering — material flows, process steps, equipment, labor, and yield — rather than from a rough analogy to a similar product. For a battery cell, that means starting from the cathode, anode, electrolyte, separator, and cell-assembly steps, and building the per-kWh cost up from there. The result is a number you can defend line by line, not a benchmark pulled from a press release.

Cost estimates aren't all built to the same rigor, though, which is where AACE International's classification system comes in.

Methodology

The AACE cost-estimate classes, Class 5 to Class 1.

AACE ranks estimates by how much engineering definition backs the number. More definition means a tighter accuracy range, and more work to produce.

Order of magnitude

Minimal process detail. Rough screening only.

-30% / +100%

Study estimate

Enough detail for feasibility studies and concept comparison.

-20% / +50%

Budget authorization

Process-level mass & energy balance. Supports capex screening and pre-FID decisions. This is where Wensura's demo model lands.

-20% / +30%

Control estimate

Detailed engineering, used to set project budgets and control costs.

-10% / +20%

Definitive estimate

Complete engineering. Used for final investment decisions.

-5% / +10%

Class 3 is the sweet spot for the decisions R&D and strategy teams actually make day to day: is this chemistry worth pursuing, does this capex clear the bar, what should we push for in a supplier negotiation. It's detailed enough to defend to a board, without requiring a finished plant design first.

How The Model Works

From mass balance to per-kWh cost.

Three things have to be true for a Class 3 estimate to be trustworthy, not just plausible.

01 · Closure

Mass & energy balance

Every input — active material, electrolyte, packaging — is reconciled against the finished cell plus process losses. Energy consumption is tracked per process step. Without closure, a cost model can silently double-count or drop material flows.

02 · Structure

Cost waterfall

Cathode, anode, electrolyte, separator, current collectors, cell housing, manufacturing labor, and pack integration are each costed independently, then summed. You can see exactly which line moved and why.

03 · Currency

Live price join

The cost stack isn't static. When cobalt, nickel, or lithium spot or contract prices move, the cathode segment — and the total — recompute against the current price, not a quarter-old snapshot.

See It Move

A price moves. The cost stack rebuilds.

Pick a market scenario below — the same recompute engine behind the homepage demo, run against a Class 3 model for NMC-811 on the public BatPaC 5.2 reference basis.

Preview

Reference prices · NMC-811 · BatPaC 5.2 pack basis

$100.92

per kWh · pack level

baseline

Anode (graphite): $8.60 / kWh

Preview · Process & TEA in build BatPaC 5.2 reference stack (NMC-811 · graphite) · metal pass-through per BatPaC's CAM cost tool · illustrative demo

Where This Stands Today

What's live, what's in build.

Market Data — time-series materials & precursor pricingLive

Battery Base — multi-model cross-checked copilotLive

Process & TEA — AACE Class 3 wizard, cost waterfall, live recomputeIn Build

Design partners run their real cell BOM through the Process & TEA module during a 2-week NDA-covered pilot. See pricing or bring your chemistry to a demo call.

TEA FAQ

Questions about the methodology.

What is an AACE Class 3 estimate?

A cost estimate built on process-level mass & energy balance detail, accurate to roughly -20%/+30%. It supports capex-screening and pre-FID decisions without requiring a complete plant engineering design.

What does mass & energy balance closure mean?

Every material and energy input is reconciled against the finished cell plus process losses. Closure is what makes the resulting per-kWh number defensible rather than a rough guess in spreadsheet form.

Which chemistries are supported?

The current demo model runs NMC-811 on the public BatPaC 5.2 reference basis. LFP, NMC-622, NCA, and custom chemistry inputs are on the near-term roadmap.

How does live pricing recompute work?

The materials pricing corpus is joined directly to the cell BOM inputs. When a tracked commodity moves, the cost stack recomputes in seconds — no manual spreadsheet rebuild.

Run this against
your actual cell chemistry.

15 minutes, no slides. Bring your BOM — we'll show the cost waterfall live.

Book a 15-min Demo

AACE Class 3 cost modelingfor battery cells.