What Needs to Be Replaced When Switching from Lead-Acid to Lithium Batteries?

[DiMaria]

When switching from lead-acid to lithium batteries, the charger and equipment matching parameters need to be replaced. Below are the differences between lead-acid and lithium batteries: Nominal Voltage: The nominal voltage of a single lead-acid battery cell is 2.0V; the nominal voltage of a single lithium battery cell is 3.6V. Internal Materials: The positive and negative electrodes of lead-acid batteries are lead oxide, metallic lead, and concentrated sulfuric acid electrolyte; the positive and negative electrodes of lithium batteries are lithium cobalt oxide, lithium iron phosphate, lithium manganese oxide, graphite, and organic electrolyte. Energy: Lead-acid batteries have 30WH/KG; lithium batteries have 150WH/KG. Electrical Characteristics: Lead-acid batteries cannot discharge at high currents and have a short lifespan; lithium batteries can discharge at high currents and have a long lifespan.

[EthanLynn]

I previously converted my lead-acid battery to a lithium battery myself, and the whole process felt quite thrilling. First, I had to replace the old battery with a suitable lithium battery, such as a lithium iron phosphate (LiFePO4) type, ensuring the size and voltage matched the original vehicle. Then, I had to install a Battery Management System (BMS), which monitors temperature and voltage to prevent overcharging and over-discharging, as lithium batteries are prone to catching fire otherwise. The charging system also needed an upgrade—the original vehicle alternator might output too high a voltage, requiring a voltage regulator or a compatible charger. Additionally, I had to check the wiring connectors; lithium batteries are much lighter, but the connectors might not match, so I used adapters to reinforce them. Finally, don’t forget safety—install a fuse to protect the circuit. After the conversion, the car starts faster, is lighter, and has a longer range, but beginners should ideally get a friend to help to avoid messing up the electrical system.

[Mitchell]

Replacing with a lithium battery is not as simple as just swapping the battery. Lead-acid and lithium batteries have different voltage characteristics, and the original vehicle charging system may not be compatible. It's necessary to check the alternator output, as too high a voltage can damage the new battery. A BMS (Battery Management System) must be installed to monitor in real-time and avoid short-circuit risks. The wiring connectors also need to be replaced, as lithium batteries are lighter but carry higher current, which can cause old connectors to overheat. It's recommended to install additional fuses and isolators to protect the circuit. The entire process should be done step by step: first disconnect the power, remove the old battery, install the new lithium battery, connect the BMS and regulator, and finally test for voltage stability. Improper modifications may cause fires or damage the vehicle's electronic systems, so proceed with caution.

[Bo]

Upgrading to lithium batteries mainly involves replacing three components: the new battery itself, selecting a lithium battery model that matches the voltage; the Battery Management System (BMS), which is the core protective device; and the charging adapter, as the original system might have excessive voltage. After installation, the vehicle becomes noticeably lighter, with faster startup response and longer lifespan. However, be cautious not to opt for cheap, low-quality accessories, as they can easily cause issues.