A one-minute painted explainer of the simulator's battery model, followed by the real-world background and where to read more.
Around nineteen hundred, about a third of the cars on American roads ran on electricity. This simulator lets you wire the battery bank of one of those early electric carriages. Each glass jar in the tray is a lead-acid cell. The model gives every cell two volts, fifty amp-hours, and fifty kilograms of weight. Link two cells in series, and their voltages add. Two plus two makes four volts, but the capacity stays at fifty amp-hours. Link the two pairs in parallel, and capacity adds instead. That's the default bank: four volts, one hundred amp-hours, and seven hundred kilograms, counting the five hundred kilogram carriage. When you press Drive, the model spins the wheels faster with more volts, and drains charge faster with more weight. So volts buy speed, amp-hours buy time, and every cell is also a heavy passenger. The driving physics is a toy, and in our test runs no bank made it over the hill. So click the S and P links, switch cells off, and watch volts, amp-hours and kilograms trade places.
Cells in series stack their voltage; strings in parallel stack their capacity. Stored energy is roughly volts × amp-hours, so the default 2-series, 2-parallel bank (4 V × 100 Ah ≈ 400 Wh) holds the same energy as all four cells in series (8 V × 50 Ah).
Every cell is modelled as 2 V, 50 Ah and 50 kg, on a 500 kg carriage. A lead-acid cell's nominal voltage really is about 2 volts; the capacity and weight are round teaching numbers, not a specific 1900 battery.
Wheel spin is proportional to bank voltage, and each physics step drains charge in proportion to total mass, regardless of speed. Real batteries drain with the current drawn, and lead-acid cells deliver less capacity at high current (Peukert's law).
Practical electric cars of the era wired dozens of cells in series to reach tens of volts. A four-cell, 8-volt maximum is a simplification for the puzzle, not a working drivetrain.
The U.S. Department of Energy notes that around 1900 electric vehicles made up about a third of the vehicles on the road, before cheap gasoline and the electric starter tipped the market.
Early electric cars, including their share of vehicles on the road around 1900.
General background on early battery-electric carriages.
Cell chemistry and the roughly 2-volt nominal cell voltage.
Why voltages add in series and capacities add in parallel.
How lead-acid capacity falls at high discharge currents, which the tool ignores.
Numbers in the video come from this simulator's simplified battery model (2 V, 50 Ah, 50 kg per cell); its driving physics is a toy and does not reflect how a real 1900 electric carriage performed.