The battery is the car
On a gas car you worry about the engine and transmission. On an EV, the battery pack is the expensive part, and its condition decides the range, the resale value and whether you will ever face a big bill.
The number to ask for is state of health, usually written SoH, shown as a percentage. It compares the battery's usable capacity today to what it had new. Above 90 percent on a car under six years old is strong. Under 80 percent deserves a serious price conversation or a walk away.
A rated range on the window sticker means nothing on a used car. The SoH reading and a real world range test do.
Why Miami changes the math
Heat ages a lithium battery faster, and heat combined with a high state of charge is the worst case. A car that spent three years parked at 100 percent in a sunny lot on Biscayne Blvd has aged more than the same car in a garage up north.
Ask how the car was charged and where it lived. Daily fast charging and long stretches at full charge both leave marks. The battery report shows the result even when the seller cannot remember the habits.
The warranty that transfers
Federal rules require the battery pack on an EV to be covered for at least 8 years or 100,000 miles, whichever comes first, and that coverage usually transfers to the next owner. Many manufacturers also promise to repair or replace a pack that drops below a set capacity, often around 70 percent, inside that window.
The clock started the day the first owner took delivery, not the day you buy it. Ask for the in service date and get the remaining coverage and the transfer terms in writing before you sign.
What an EV battery health check does
We connect to the car's battery management system and read the state of health, the cell balance across the pack, stored fault codes and the condition of the battery cooling system. Miami is hard on that cooling system, and a weak one is what turns normal aging into fast aging.
You get a written report you can hand to the seller or keep. It is yours, whether you buy the car or not.
Beyond the battery
EVs are heavy and quick, so they wear tires faster than you expect. Check tread on all four and look for uneven wear that points to alignment.
Brakes on an EV can rust from underuse because the motor does most of the stopping. The 12 volt battery still exists and still dies in the heat. The charge port door, the charging cable, the cabin filter and any open software recalls belong on the list too.
A pre-purchase inspection covers all of this alongside the battery report, in one visit.
Using the report at the negotiating table
A clear SoH number and a written list of what the car needs are the strongest tools you have. If the battery is at 85 percent and the tires are done, that is a specific dollar conversation, not a feeling.
Ask the seller to fix the items or take them off the price. If they refuse both, the report already told you what to do. Walk.