E-FAST 20A Smart Car Battery Charger 12V/24V — LiFePO4 & Lead-Acid with Desulfator, 7-Stage Fast Charge

The E-FAST 20A Smart Car Battery Charger is a high-power, microprocessor-controlled 12V/24V charger and maintainer with dedicated LiFePO4 and lead-acid modes plus a pulse desulfation repair function.

This compact charger delivers fast, safe charging for a wide range of batteries used in cars, trucks, RVs, boats and agricultural equipment. With a 20A output on 12V systems (10A on 24V), seven-stage charging logic, auto-memory and active cooling, it’s designed to bring large-capacity batteries back to service and keep them at optimal state-of-charge without overcharging. The unit also includes a repair/desulfation cycle to help recover sulfated lead-acid batteries and multiple built-in protections for unattended use.

How quickly will this charger restore a flat battery?

The E-FAST 20A charger provides rapid replenishment for large batteries. On 12V mode it supplies up to 20 amps, which can fully charge a 100Ah battery in roughly 5–6 hours under normal conditions—about twice as fast as many 10A chargers. For 24V battery banks the charger delivers 10A.

• 20A max output for 12V, 10A for 24V
• Estimate: 100Ah battery ≈ 5–6 hours from low state
• Suitable for batteries up to 300Ah in capacity

Will it work with my lithium or lead-acid battery type?

Yes—this charger is programmed for both LiFePO4 lithium batteries and multiple lead-acid chemistries. Choose the correct mode for LiFePO4, AGM, GEL, SLA, wet or deep-cycle batteries and the charger will apply tailored voltage and charge profiles to protect battery health. The Auto-Memory feature remembers your last selection for convenience across sessions.

• Dedicated LiFePO4 algorithm to protect lithium cells
• Lead-acid support: AGM, GEL, SLA, wet, deep-cycle
• Auto-Memory stores last selected charging mode

Can it revive an old or sulfated battery?

The charger includes a Repair Mode that uses pulse desulfation to help break down sulfate buildup on lead-acid battery plates. This 16-hour cycle is intended to restore capacity to idle or stratified batteries that suffer from sulfation, potentially extending service life and delaying replacement. Results vary by battery condition and age.

• Repair Mode: advanced pulse desulfation cycle
• 16-hour dedicated repair program for lead-acid batteries
• Best for batteries with early-stage sulfation or long storage discharge

Is the charger safe to leave connected overnight or during storage?

Yes—the E-FAST 20A offers comprehensive protections and smart maintenance stages so it can be used for long-term maintenance. Over-charge, reverse polarity, short-circuit and over-temperature safeguards protect both the battery and the charger. An internal cooling fan helps dissipate heat during high-amp operation.

• Seven-stage microprocessor charging prevents overcharging
• Built-in protections: reverse polarity, short circuit, over-temp
• Active cooling fan for sustained 20A performance

Who is this for: The E-FAST 20A charger is intended for vehicle owners and technicians who need faster, smarter charging for medium-to-large battery banks—owners of trucks, RVs, boats, marine electronics, agricultural machines and deep-cycle systems. It’s a good fit when you require versatile compatibility (LiFePO4 and multiple lead-acid chemistries), routine maintenance over long storage periods, or the ability to attempt recovery of sulfated lead-acid batteries. Choose this unit when you want higher charging current, automated charging intelligence and safety features for unattended charging sessions.