Dear Valued Customers and Industry Partners, As we embrace the fruitful golden autumn in October, Fuyang Electronics sincerely invites you to visit us at the 138th China Import and Export Fair (Canton Fair). Let us gather in the vibrant flower city of Guangzhou, China. At this global trade feast
Grand DebutFuyuang Pioneers at 2025 China International Bicycle Expo, Unlocking Next-Gen Charging Technology for E-BikesIntroduction: A Global Stage for Technological RevolutionOn May 5, 2025, the world’s attention will converge at the Shanghai New International Expo Center as the China Internatio
【Canton Fair Day 1 Highlights】Fuyuang’s Cutting-Edge Charging Technology Draws Global Buyers’ PraiseOn April 15, 2025, the 137th China Import and Export Fair (Canton Fair) officially opened at the Pazhou Exhibition Center in Guangzhou.
At FYCharger, we provide a full series of Lead-acid Battery Chargers designed for 12V, 24V, and other customizable voltage requirements. Our chargers are engineered with intelligent CC/CV charging algorithms, ensuring accurate voltage control, fast charging efficiency, and long-term battery protection.
This category includes chargers compatible with multiple lead-acid battery types such as Flooded Lead-acid, AGM, GEL, and Deep Cycle batteries. Whether you need a charger for automotive maintenance, solar storage systems, UPS backup applications, or electric mobility equipment, we deliver reliable and high-performance charging solutions for both home and industrial use.
Our chargers support a full range of lead-acid battery types, including Flooded, AGM, GEL, and Deep Cycle models—ideal for vehicles, solar systems, marine batteries, and industrial equipment.
Built with smart MCU control, the charger automatically adjusts between Bulk, Absorption, and Float stages, ensuring fast charging, stable current output, and long-term battery health.
Every lead-acid charger includes:
Over-current protection
Over-voltage protection
Over-temperature protection
Reverse polarity protection
Short-circuit protection
Automatic stop for overcharge protection
This ensures safe, worry-free charging in both home and commercial environments.
Designed with durable components and efficient heat dissipation, our chargers offer stable operation even during long-term use. Suitable for heavy-duty and high-frequency charging tasks.
We support a wide range of customizations:
Output voltage & current
Housing design
Charging cables & connectors
Logo printing
Packaging customization
Perfect for brands, wholesalers, and industrial project suppliers.
| Feature | Standard Charger | Smart Multi-stage Charger | Industrial Heavy-duty Charger |
|---|---|---|---|
| Battery Types | Basic lead-acid | AGM / GEL / Deep Cycle | All lead-acid batteries |
| Charging Speed | Normal | Fast | Very fast |
| Protection | Basic | Full protections | Industrial protections |
| Application | Home use | Vehicles & solar systems | Factories, workshops |
| Recommended For | Low frequency use | Daily use | Long-term heavy-duty use |
Our chargers can be used for:
Automotive batteries (car, motorcycle, truck)
Marine lead-acid batteries
Solar energy storage systems
UPS backup power
Electric scooters, wheelchairs, and mobility devices
Industrial machinery & equipment
Deep cycle battery maintenance
RV & boating power systems
Whether for home maintenance or industrial power solutions, our lead-acid chargers provide reliable and efficient charging performance.
Explore our full selection of 12V / 24V smart lead-acid chargers below. Each product features stable output, user-friendly operation, and multiple safety protections—ideal for various battery capacities and applications.
Selecting the correct charger is essential for battery performance and safety. Here are the key factors to consider:
Choose a charger that matches your battery voltage:
12V chargers → cars, motorcycles, small solar systems
24V chargers → trucks, forklifts, mobility devices
36V / 48V chargers → industrial machines (customizable)
The charger current should be around 10% of battery capacity.
Example: A 100Ah battery requires a 10A charger.
Ensure compatibility with:
Flooded / Wet Lead-acid
AGM
GEL
Deep Cycle
Different environments require different chargers:
Indoor maintenance → standard smart charger
Outdoor / transport use → rugged & waterproof charger
Industrial use → high-current, long-duty-cycle charger
If unsure, our technical team can recommend the best model based on your battery specifications.
A lead-acid battery charger works by supplying controlled voltage and current to restore the battery’s chemical energy. The charger monitors the battery’s voltage, internal resistance, and temperature to determine the correct charging profile automatically.
Here’s how the process works:
When the battery is deeply discharged, the charger delivers a steady current to quickly replenish capacity.
This helps bring the battery up to its normal operating voltage.
Once the battery reaches its optimal charging voltage, the charger switches to constant voltage and gradually reduces the current.
This prevents overcharging and protects the battery plates.
Smart chargers automatically detect:
Battery type (AGM, GEL, Flooded)
Battery voltage (12V, 24V, etc.)
Reverse polarity
Over-voltage / over-current conditions
Temperature changes
This ensures safe, efficient charging without damaging the battery.
Some chargers adjust charging voltage based on ambient temperature.
Higher temperature → lower charging voltage
Lower temperature → higher charging voltage
This extends battery life and improves charging accuracy.
Modern lead-acid battery chargers use multi-stage charging to maximize performance, safety, and battery longevity.
The number of stages may vary (3-stage, 4-stage, 7-stage), but the essential functions are similar.
Below is the universally accepted charging framework:
The charger delivers maximum current.
Battery voltage rises rapidly.
This stage restores 70–80% of the battery capacity.
This is the fastest phase and prepares the battery for controlled top-up charging.
Voltage is held at the optimal level (typically 14.4–14.7V for a 12V battery).
Current gradually decreases.
The remaining 20–30% of capacity is restored.
This prevents overheating and protects battery plates from damage.
Voltage is reduced to a safe maintenance level (typically 13.5–13.8V).
Keeps the battery at 100% without overcharging.
Ideal for long-term maintenance or standby systems (UPS, solar storage, RV batteries).
Float charging is essential for batteries that remain idle for long periods.
Used mainly for Flooded or deeply sulfated batteries.
Applies a controlled higher voltage for a short time.
Balances cell voltage and removes mild sulfation.
Can extend battery life when used appropriately.
Not recommended for GEL or some AGM batteries unless specified by the manufacturer.
If the battery is extremely low (below ~10V):
Charger delivers a small, controlled current.
Safely raises battery voltage before normal charging begins.
Protects the battery from sudden current surge.
This stage is found in advanced smart chargers.
| Stage | Purpose | Voltage (12V battery) | Characteristics |
|---|---|---|---|
| Bulk | Fast charging | Rising ~12.0 → 14.4V | Max current, restores 70–80% |
| Absorption | Controlled top-up | 14.4–14.7V | Constant voltage, decreasing current |
| Float | Long-term maintenance | 13.5–13.8V | Prevents overcharging |
| Equalization (optional) | Cell balancing & desulfation | 15.5–16V (flooded only) | Not for GEL/AGM |
| Soft Start (optional) | Safe low-voltage recovery | <10–12V | Gentle current introduction |
Our lead-acid battery chargers comply with international safety and quality certifications, including:
CE / RoHS / FCC
UL-compliant components
ISO9001:2015 certified production
Strict QC inspection before shipping
These certifications ensure product safety, EMC stability, and eco-friendly manufacturing.
They support Flooded Lead-acid, AGM, GEL, and Deep Cycle batteries commonly used in vehicles, solar systems, boats, UPS systems, and industrial equipment.
Yes, we provide 12V, 24V, and customizable voltage options such as 36V or 48V for industrial applications.
Yes. With automatic Float Charging, the charger maintains a safe voltage level without overcharging the battery.
Absolutely. We can customize voltage, current, housing, connectors, cables, packaging, and branding.
Yes. They are widely used in off-grid solar systems, energy storage batteries, and backup power systems.
A smart multi-stage lead-acid battery charger is recommended.
It uses an automatic charging algorithm that includes:
Bulk charging (fast power delivery)
Absorption charging (controlled top-up)
Float charging (maintains full charge safely)
This type of charger prevents overcharging, reduces sulfation, and extends battery life. It also works with Flooded, AGM, GEL, and Deep Cycle batteries.
The proper method is to use a smart CC/CV (Constant Current / Constant Voltage) charger and follow these steps:
Use a charger that matches your battery’s voltage (12V, 24V, etc.).
Connect positive to positive and negative to negative.
Allow the charger to run automatically through Bulk → Absorption → Float stages.
Avoid fast-charging unless recommended for your battery type.
Charge in a ventilated area to avoid gas buildup (for flooded batteries).
This ensures safe and efficient charging.
A 12V lead-acid battery is considered fully charged at:
12.6V – 12.8V (resting voltage)
14.4V – 14.7V during charging (depending on type)
AGM and GEL versions may differ slightly, but 12.6–12.8V is the standard full-charge resting voltage.
Yes, but only if the charger has automatic float mode.
A traditional, non-regulated trickle charger can overcharge the battery and cause plate damage.
A smart trickle charger that enters float mode (13.5–13.8V) is safe for long-term maintenance charging.
The 80/20 rule states:
Charge a battery up to 80%
Avoid discharging it below 20%
For lead-acid batteries, this helps prevent sulfation and extends battery lifespan, especially for deep-cycle models.
12.2V is not dead, but it indicates:
50% state of charge
The battery should be recharged soon
A 12V lead-acid battery is considered “dead” when it drops below 11.8V – 11.9V.
Sometimes, yes.
If the battery is only sulfated, a charger with desulfation or repair mode may restore it.
However, if:
the plates are damaged
cells are shorted
the battery cannot hold voltage
Then it cannot be restored.
Smart chargers can often revive lightly sulfated batteries.
Use a multimeter and measure resting voltage (battery disconnected for at least 1–2 hours):
12.6V – 12.8V = Full
12.4V = ~75%
12.2V = ~50%
12.0V = ~25%
11.8V or less = Dead
You can also test under load to check battery health.
A lead-acid battery can sit unused for 3–6 months, but it will self-discharge.
For storage:
Recharge every 1–3 months
Use a maintenance (float) charger to keep it healthy
Store in a cool, dry place
AGM and GEL batteries last longer in storage than flooded ones.
Check the following:
12.6V–12.8V resting = healthy
Below 12.4V = losing capacity
A healthy battery maintains above 9.6V under load.
Excessive heat or rising voltage can indicate internal failure.
12.0V means the battery is at 25% state of charge.
Recharge it first and retest:
If voltage returns to 12.6–12.8V → still good
If it drops quickly after charging → battery is failing
Only replace if it cannot hold charge.
14.7V is normal for charging certain types of lead-acid batteries (especially AGM).
However:
Going above 15V can cause overheating and water loss in flooded batteries.
Always use a charger that matches your battery type.
Yes and no.
A non-smart trickle charger can overcharge and damage the battery.
A smart float charger that maintains 13.5–13.8V is safe for long-term connection and is recommended for stored vehicles and backup systems.
Yes.
SLA, AGM, and GEL batteries require a smart charger that:
Limits voltage
Controls current
Automatically switches to float mode
Prevents overcharging
Never use a manual automotive charger on sealed batteries.
A 12V lead-acid battery at 50% charge reads:
12.2V (resting voltage)
This number is widely used in battery monitoring charts.
A 12V battery is considered dead when it falls to:
11.8V – 11.9V (resting)
At this point, sulfation increases rapidly, and the battery must be recharged immediately.
A healthy fully charged 12V battery should read:
12.6V – 12.8V (resting)
If the reading is significantly below this, the battery needs to be charged or may be failing.
