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For Students · Battery Thermal Management

Battery Thermal Management for a cooling load

Built for students learning it for a class or exam. See the concept move instead of memorizing formulas — and check your homework intuition. Simulate a cooling load live below — adjust the inputs and watch it respond, right in your browser.

Battery Storage

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Battery Energy StorageLive

capacity, efficiency & backup

Controls

Presets

Capacity (kWh)

Round-trip efficiency (%)

Depth of discharge (%)

Daily load from battery (kWh)

A battery's rated capacity is not all usable: depth-of-discharge limits protect its life, and round-trip efficiency means some energy is lost charging and discharging. What actually reaches your home is capacity × depth-of-discharge × round-trip efficiency. Together with cycle life, these set backup duration and the cost per stored kilowatt-hour.

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Data Inspector

Usable capacity12.2 kWh

Delivered / cycle10.9 kWh

Backup time26.2 hr

Lifetime throughput66 MWh

Governing equation

E_{del} = C \cdot DoD \cdot η_{r t} = 13.5 \times 0.90 \times 0.90 = 10.9 kWh

Reading this result: Usable energy is capacity × depth-of-discharge × round-trip efficiency, so only 10.9 of 13.5 kWh (81%) reaches your home each cycle — the discharge limit removes more here than efficiency does.

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Thermal Resistance

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Composite Wall Heat TransferLive

R-value & U-value

Controls

Presets

Drywall (mm)

Insulation (mm)

Brick (mm)

Inside temp (°C)

Outside temp (°C)

Heat flows through a wall like current through resistors in series. Each layer's thermal resistance is its thickness over its conductivity; adding them gives the total R-value, and the heat flux is the temperature difference divided by it. Insulation, with very low conductivity, dominates the R-value — the steep temperature drop shows where it does its work.

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Data Inspector

Total R-value2.71 m²K/W

U-value0.37 W/m²K

Heat flux9.6 W/m²

Governing equation

R = \sum \frac{L _{i}}{k _{i} A} = 2.71 \frac{m ^{2} K}{W}, Q = \frac{Δ T}{R} = 9.6 \frac{W}{m ^{2}}

Reading this result: The insulation layer carries the most thermal resistance, so the temperature falls most steeply across it. A total R-value of 2.71 m²K/W lets 9.6 W/m² flow for this 26°C difference.

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Frequently asked questions

Is this good for students?: Yes — this version of "Battery Thermal Management for a cooling load" is framed for students learning it for a class or exam. See the concept move instead of memorizing formulas — and check your homework intuition.
Do I need to install anything?: No. It runs in any modern browser, free, with no account required.