Revolutionary Solutions: Uninterrupted Emergency Power
Improving Automobile Battery Life with the Right Chemistry
The auto industry is rapidly shifting towards more electrification, with the growth of start-stop systems, emergency call (eCall) telematics, and hybrid vehicles driving the need for advanced battery management systems. These systems not only need to charge batteries safely but also extend their lifespan.
Choosing the right battery chemistry from the many options available can be tough. Each type of battery comes with its specific charging requirements.
Understanding Li-ion Batteries
Li-ion batteries are rechargeable, where lithium ions move between the negative and positive electrodes during discharge and charging cycles. These batteries use an intercalated lithium compound for the electrodes, with an electrolyte facilitating ionic movement. While Li-ion batteries offer high energy density, they typically have low power.
The nominal voltage for charging a Li-ion battery is usually 3.6V, with the upper limit at 4.1V and the lower at 2.2V. It’s crucial to charge these batteries according to manufacturer guidelines to ensure safety and reliability. Charging outside the specified voltage levels or recommended temperature ranges can damage the battery.
Within the upper and lower voltage bounds, a constant charge current, limited to the manufacturer’s specifications, is recommended to avoid battery damage. Below the lower cut-off voltage, a very low current—about 10% of the usual charge current—is advised. This pre-charging step helps deeply depleted batteries recover and guards against overheating, especially if the low voltage was caused by an internal short circuit.
Overcharging a Li-ion battery, even for short periods, can diminish its materials and reduce its capacity and lifespan. Prolonged overcharging may lead to serious consequences like battery failure or even combustion.
Temperature Considerations
Charging Li-ion batteries within a specific temperature range is critical. Charging below freezing can cause metallic lithium to coat the anode, which can’t be removed and harms the battery’s longevity. High temperatures during charging cycles can severely cut down the battery’s capacity. Just a few cycles from 0% to 100% charge at heightened temperatures can decrease capacity by over 90%.
A practical solution to follow the manufacturer’s charging guidelines is to use a dedicated charger. These chargers can quickly and safely charge the battery, offering programmable constant current and set upper and lower cut-off levels, suitable for most Li-ion batteries. Additionally, a cell temperature monitor with an NTC thermistor ensures charging only occurs within the specified temperature range.
Exploring Lithium Iron Phosphate (LFP) Batteries
LFP batteries, a type of rechargeable battery, utilize nanoscale LiFePO4 material for the cathode. These batteries have their unique characteristics and are another option to consider when selecting the right battery chemistry for automotive applications.
