Ultra long cycle life and lightweight LiFePO4 12V 20Ah Battery for Access Control Systems, Electronic Locks and Card Readers, ire Alarm Systems, Solar Street Lights
- 10x the life of traditional SLA batteries.
- 3x the durability of average lithium competitors.
- Near-zero maintenance costs for the next decade and a half.
- Safe & Stable: UL-listed cells and advanced thermal management.
- Rapid Recharge: 4x faster charging than SLA, ensuring zero-downtime for critical applications.
Flexible order quantity to support prototype testing and mass production.
Batteries certified to UL,CE,UN38.3,MSDS,ROHS,IEC62133 and more global standards.
Customized size,current, case and working temperature.
7-10 days quick delivery.
Top 12V 20Ah LiFePO4 Battery Manufacturers in China
A 12V 20Ah LiFePO4 battery is a type of rechargeable lithium iron phosphate battery, consisting of a total of eight 26700 or 26650 cells in series and parallel to reach 12.8V nominal voltage and 20Ah nominal capacity. It’s a high performance lithium battery, designed primarily as a lightweight and smaller replacement for traditional 12V 20Ah Sealed Lead Acid (SLA) batteries.
12V 20Ah rechargeable lithium battery has a nominal voltage of 12.8V, cut-off voltage of 9V and maximum charge voltage of 14.6V.Compatible with most standard 12V electronics and chargers, the 12V 20Ah lithium battery is widely used in Access Control Systems, Electronic Locks and Card Readers, ire Alarm Systems, Solar Street Lights.
| Parameter 1 | Value 1 | Parameter 2 | Value 2 |
|---|---|---|---|
| Nominal Voltage | 12.8V | Capacity | 20Ah |
| Energy | 256Wh | Discharge Cut-off Voltage | 8V |
| Max Charge Current | 20A | Max Discharge Current | 40A(≤5s) |
| Cycle Life | >3000 | Self-discharge Rate | 2% |
| Dimensions | 181 x 77 x 167mm | Weight | 2.8Kg |
| Operating Temperature | -20℃ to 60℃ | Storage Temperature | 0 to 25ºC |
| Protection | Overcharge, Overdischarge, Overcurrent / Short-Circuit, Temperature, Cell Balancing | ||
LiFePO4 Battery Advantage
- Ultra-Long Lifecycle: Over 3,000 deep cycles, lasting 10 times longer than traditional lead-acid batteries.
- Lightweight: Typically uses the standard SLA case size, but 1/3 weight of the traditional 12V 20Ah lead acid battery.Drop-in replacement for alarm system and UPS units.
- Cost Per Cycle: Lifepo4 battery is only 1/4 cost of traditional lead acid battery in long run term.
- 100% Usable Capacity： Supports 100% DOD, delivering 40% more usable energy than equivalent lead-acid packs
- Smart BMS Protection： Integrated Smart BMS prevents overcharging and shorts, ensuring absolute safety for users.
- Eco-Friendly & Compliant ： Non-toxic, sustainable, and fully certified with CE, UN38.3, and RoHS standards.
Lifepo4 battery Feature
Superior lifepo4 battery features only 3% self discharge rate per month. Ensure your equipment always ready to go even after several months of storage.Eliminate regular maintenance in water filling and acid check compared to traditional lead-acid batteries.
Lifepo4 battery is inherently safe chemistry against thermal runaway.
The integrated smart BMS can protect against extreme conditions to ensure ultimate safety for different power solutions.
The 12V lifepo4 battery adopts a modular design for flexible scalability.You can easily connect multiple 12V battery modules in series or parallel ,tailor made for your increasing power demand.
Why Choose VTCBATT?
VTCBATT not only focuses on customized design and excellent service to meet the diverse demands of different customers, but also devotes itself to precise and standardized manufacturing in every process to ensure the highest-quality batteries. Meanwhile, VTCBATT will provide comprehensive support from pre-sales to after-sales, focusing on customers’ feedback to establish long-term and win-win cooperation. VTCBATT professional sales and technical engineer teams will be your best custom battery experts to assist with reliable and fast services at any time.
From the raw materials mixing to the cell test, VTCBATT adopts an automatic manufacturing process to maximize production efficiency and enhance the batteries quality, safety, and reliability. The entire manufacturing process is monitored and 100% tested before flowing to the next procedure to ensure zero defects before delivery.
Over the past 20 years, VTCBATT has built strong partnerships with customers in more than 50 countries worldwide. With reliable quality, responsive service, and tailored battery solutions, we have earned the trust of our clients—many of whom have maintained long-term cooperation and lasting friendships with us for over a decade. Together, we continue to grow and move forward toward a brighter future.
Application
The VTCBATT LiFePO₄ (Lithium Iron Phosphate) battery is widely used in energy storage systems, electric mobility, backup power solutions, solar power systems, RVs, marine applications, and industrial equipment, where high safety, long cycle life, and stable power output are essential. With a modular and compact design, it is ideal for Access Control Systems, Electronic Locks and Card Readers, ire Alarm Systems, Solar Street Lights.
This battery supports series and parallel configurations, with customized voltage, capacity, and intelligent BMS to precisely match your application requirements. Featuring excellent thermal stability, low internal resistance, deep cycle capability, and superior safety performance, the VTCBATT 12V 20Ah LiFePO₄ battery ensures efficient energy management, long service life, and reliable operation for both consumer and industrial applications.
Provides stable standby power for access control systems, ensuring secure entry management during outages.
Delivers reliable energy for security cameras, supporting continuous surveillance and clear monitoring performance.
Ensures uninterrupted backup power for UPS systems, protecting essential equipment from sudden power failures.
Supports dependable access control operation with long cycle life and stable voltage for daily security.
Powers electronic locks reliably, maintaining secure locking performance and fast response in critical situations.
Supplies consistent backup energy for fire alarm systems, helping maintain emergency warning readiness.
Keeps fire alarm systems operating safely with dependable standby power and long-lasting discharge performance.
Provides steady power for electronic locks, ensuring secure access control and dependable emergency operation.
The runtime of 12 volt 20Ah battery depends on the load device and battery chemistry.
- Battery Chemistry: A 12 volt battery 20Ah maintains 240Wh of total energy.
A lead-acid 12V 20Ah battery can only discharge 50% of the total energy, with an actual 120Wh usable power.
The Lifepo4 battery 12V 20Ah can discharge almost the total 240Wh energy in 100% depth of discharge.
- Power Load: For a 60W large tablet load, a LiFePO4 12V 20Ah battery can last nearly 4 hours in 100% usable power in our field test. In contrast, a traditional 12V 20Ah lead-acid battery can only last 2 hours due to only 50% usable power.
12V 20Ah LiFePO4 Runtime Reference Table
| Device Application | Power (Watts) | Current Draw (Amps) | LiFePO4 Runtime (100% DOD) | Lead-Acid Runtime (50% DOD) |
| LED Camp Lights | 10W | 0.8A | ~24.0 Hours | ~12.0 Hours |
| CCTV / Security Camera | 15W | 1.2A | ~16.0 Hours | ~8.0 Hours |
| Fish Finder / GPS | 25W | 2.0A | ~9.5 Hours | ~4.5 Hours |
| CPAP Machine | 40W | 3.1A | ~6.0 Hours | ~3.0 Hours |
| Electric Scooter / Toy Car | 120W | 9.4A | ~2.0 Hours | ~1.0 Hour |
| Large Tablet/Laptop (via Inverter) | 60W | 4.7A | ~4.0 Hours | ~2.0 Hours |
| Car Fridge (Compressor) | 45W | 3.5A | ~5.5 Hours | ~2.7 Hours |
| Trolling Motor (Small) | 200W | 15.6A | ~1.2 Hours | ~0.6 Hours |
12V 20Ah LiFePO4 battery provides 256Wh (Watt-hours) of total energy. With 100% usable power, it is the ideal power source for many sectors in outdoor marine, medical mobility, industrial safety, and hobbies.
12V 20Ah LiFePO4 Battery Application Table
| Sector | Specific Application | Why 12V 20Ah is the Best Choice |
| Outdoor & Marine | Kayak Trolling Motors | Provides ~1-2 hours of thrust without the 15kg weight of lead-acid. |
| Fish Finders & GPS | Powers high-end sonar (Garmin/Lowrance) for 2+ full days of fishing. | |
| Portable Solar Kits | Ideal size for 50W-100W solar panels for off-grid camping. | |
| Medical & Mobility | CPAP Machines | Powers a CPAP for 1-2 nights, making it perfect for travel/power outages. |
| Mobility Scooters | Direct “drop-in” upgrade for 18Ah/20Ah SLA batteries; doubles the range. | |
| Electric Wheelchairs | Reduces vehicle weight by ~5kg, making the chair easier to handle. | |
| Industrial & Safety | CCTV / Remote Security | Powers a 15W camera setup for ~16 hours during a blackout. |
| UPS / Backup Power | Reliable backup for small servers, Wi-Fi routers, and alarm panels. | |
| Remote Sensors (IoT) | High cycle life (6000+) means less frequent maintenance in the field. | |
| Hobbies & DIY | Ham Radio (HF/UHF) | “Pure power” with no electrical noise—perfect for field day operations. |
| Robotics & Go-Karts | High peak current (40A pulse) handles motor startup surges easily. | |
| Electric Lawn Mowers | Efficient replacement for small 12V lead-acid garden equipment. |
12V 20Ah means the voltage is 12V and the capacity is 20Ah.
– 12V (Voltage): The nominal voltage is 12.8V with steady voltage output at 12.0V-13.0V, making it compatible with standard 12V electronics and chargers.
– 20Ah (Capacity): Stands for 20 Amp-hours, meaning it can theoretically deliver 1 Amp of current for 20 hours or 20Amps for 1 hour.
– LiFePO4: The chemistry (Lithium Iron Phosphate) is inherent-safe materials and the most durable type of lithium-ion battery.
The charging time for a 12V 20Ah lithium battery depends primarily on the charger’s output current (Amperage) and the battery’s Depth of Discharge (DOD).
1. Charge Time Table
Formula: Charging Time (hrs) = [Battery Capacity (Ah) / Charge Current (A)] × 1.2 (Efficiency Factor)
12V 20Ah Lithium Battery Charge Time Table
| Charge Current (A) | Charging Type | Estimated Time | Recommended Scenario |
| 2.0A | Trickle Charge (0.1C) | 12.0 Hours | Best for maximizing battery cycle life. |
| 4.0A | Standard Charge (0.2C) | 6.0 Hours | Ideal for daily maintenance and longevity. |
| 6.0A | Moderate Charge (0.3C) | 4.0 Hours | Balanced speed; recommended for frequent use. |
| 10.0A | Rapid Charge (0.5C) | 2.4 Hours | Only for high-performance cells with compatible BMS. |
Note: The LiFePO4 battery uses CC/CV (Constant Current/Constant Voltage) charging stages. During the last 10% energy charging process, it will take a longer time for the BMS to balance each cell.
- Depth Of Discharge(DOD)
The deeper the battery was discharged in its last cycle, the more energy is required to charge back to 100% capacity in the next new cycle. A battery discharged to 100% will take twice the time to charge as one discharged to 50%.
12V 20Ah LiFePO4 Charge Time Table (by DOD)
| Depth of Discharge (DOD) | 2A Charger (Trickle) | 4A Charger (Standard) | 10A Charger (Fast) | Remaining SOC |
| 100% (Empty) | 12.0 Hours | 6.0 Hours | 2.4 Hours | 0% |
| 80% (Deeply Used) | 9.6 Hours | 4.8 Hours | 1.9 Hours | 20% |
| 50% (Half Empty) | 6.0 Hours | 3.0 Hours | 1.2 Hours | 50% |
| 30% (Lightly Used) | 3.6 Hours | 1.8 Hours | 0.7 Hours | 70% |
| 10% (Top-off) | 1.2 Hours | 0.6 Hours | 0.2 Hours | 90% |
Featuring a maximum continuous 1C(20A) current, the battery can output a maximum of total energy 256Wh(12.8Vx20Ah). In 2C(40A) surge current, it can output 512Wh burst power for 3-5 seconds. The table below clearly shows the technical parameters and the normal values.
| Parameter | Normal Value | Description / Note |
| Nominal Voltage | 12.8V | The standard operating voltage for 4 cells in series. |
| Full Charge Voltage | 14.4V – 14.6V | Voltage while connected to a LiFePO4 smart charger. |
| Resting Voltage | 13.3V – 13.6V | Voltage when 100% charged and disconnected from the charger. |
| Low Voltage Cut-off | 10.0V | The Smart BMS will shut down output to protect the cells. |
| Standard Discharge Current | 4A – 10A | Ideal range for maximum cycle life (6,000+ cycles). |
| Max Continuous Current | 20A (1C) | The maximum steady current the BMS allows indefinitely. |
| Peak / Surge Current | 40A (2C) | Supported for 3–5 seconds (useful for motor startups). |
| Continuous Power Output | ~256W | Calculated as 12.8V×20A. |
No. A standard 12V 20Ah lithium battery can’t be used as a motorcycle starting battery.
– Standard Deep Cycle 12V 20Ah: Designed for continuous and long-lasting power in 1C(20A) continuous and 2C(40A) pulse power output.
–Motorcycle starting battery 12V 20Ah: Engineered for massive 10C(200A) to 20C(400A) cranking amps to start the motorcycle engines in seconds.
The two battery types have significant differences in discharge current, runtime, cell rate design, BMS design, lifespan design, main applications, and voltage behavior.
Comparison: 12V 20Ah Deep Cycle vs. Starter Lithium Battery
| Feature | 12V 20Ah Deep Cycle Battery | 12V 20Ah Starter Battery |
| Discharge Current | Steady & Low: Typically 20A (1C) continuous. | High Burst: 200A – 400A (10C – 20C) for cranking. |
| Runtime (Last Time) | Long Duration: Designed to run a small load for 5–20 hours. | Short Burst: Designed to work for only 3–5 seconds at a time. |
| Cell Rate Design | Energy Cells (1C/2C): Focus on maximum storage and capacity. | Power Cells (15C/25C): Focus on instant surge and high current. |
| BMS Difference | Safety Focused: Cut-off triggers at >30A to protect cell life. | High-Current Passthrough: Specially tuned to allow massive surges. |
| Lifespan Design | 2,000 – 6,000 Full Cycles: Built to be drained to 0% daily. | Low Cycle Life: Not meant for deep draining; focuses on engine starts. |
| Main Application | Fish finders, CPAP, Solar, Trolling motors, Security. | Motorcycles, ATVs, Jet Skis, and Car Engine Starting. |
| Voltage Behavior | Very flat voltage; stays strong until empty. | High voltage drop allowed during the split-second start. |
12V 20Ah lithium battery is divided into two different battery types: the 12V 20Ah deep cycle battery and the motorcycle battery 12V 20Ah. They maintain different max continuous discharge currents.
-12V 20Ah Deep Cycle Battery: Designed for 1C(20A) maximum continuous discharge current and 2C(40A) peak discharge current within 5 seconds.
-12V 20Ah Motorcycle Starter Battery: Designed for 2C-3C(40A-60A) continuous discharge current and 10C-20C(200A – 400A) cold cranking amps.
Their difference in max continuous discharge current is due to the differences in cell rate and BMS. The motorcycle starter battery uses the high rate cells and a BMS for high-burst current
Deep Cycle BMS VS Starting BMS
| Feature | Deep Cycle BMS | Starting BMS |
| Primary Goal | Longevity & Safety. Protects the cells for 6,000+ cycles. | Power & Performance. Delivers massive energy for ignition. |
| Current Handling | Restricted. Designed for steady, low current (e.g., 20A–30A). | High-Burst. Allows massive surges (200A–400A) for 3–5 seconds. |
| Over-Current | Strict. Shuts down instantly if the load is too high to prevent overheating. | Tolerant. Ignores massive spikes to ensure the engine starts. |
| Voltage Cut-off | Precise. Cuts off early (~10.5V) to prevent deep-drain damage. | Flexible. Allows voltage to drop lower (~9V) during the split-second crank. |
| Best For | Trolling motors, Solar storage, and Security backup. | Motorcycles, ATVs, and Marine engine starting. |
Yes.VTCBATT 12V 20Ah lifepo4 battery packs are in a modular design to support series and parallel connections to create a 48V system or different power demands.
12V 20Ah Battery Connection Configurations
| Configuration | Wiring Type | Final Voltage | Final Capacity | Total Energy (Wh) | Best For |
| 1 Battery | Single | 12V | 20Ah | 240Wh | Small 12V electronics, fish finders. |
| 2 Batteries | Series | 24V | 20Ah | 480Wh | 24V trolling motors, small solar kits. |
| 2 Batteries | Parallel | 12V | 40Ah | 480Wh | Extended 12V runtime (RVs, camping). |
| 3 Batteries | Series | 36V | 20Ah | 720Wh | 36V electric scooters or e-bikes. |
| 4 Batteries | Series | 48V | 20Ah | 960Wh | 48V off-grid inverters, backup power. |
| 4 Batteries | Parallel | 12V | 80Ah | 960Wh | Large 12V systems (van life, boat house bank). |
| 4 Batteries | Series-Parallel | 24V | 40Ah | 960Wh | Balanced 24V systems with higher runtime. |
Professional Installation Guidelines:
– Use the same batteries from the same batch.
-Use the same wiring cable in length and thickness.
-Before connecting, fully charge each battery to 100% using the same charger.
-Test all the batteries to make sure their start voltage are at the same voltage level.
Following the diagram for parallel and series wiring.
Many reasons are causing the battery to read 0V after long storage.
-Self Discharge: Even during storage, the 20 Ah 12V batteries and their internal BMS are still consuming energy continuously. Featuring a self-discharge rate at 2%-3% per month, the battery should be regularly charged every 6 months.
-BMS Protection: For long-term storage, a low SOC battery can be easily overdischarged, triggering the BMS to protect against overdischarge and causing 0V output.
Solutions to wake up a 0V battery:
-Use 0V Activation Charger: Use the smart charger supporting 0V charging.
Even when the BMS is protected against overdischarge wth 0V output, it can still activate the BMS to recover normal charging.
-Parallel Jump Connection: Connect with a good 12V 20Ah battery in parallel for 15-60 seconds. The flowing surge current will trigger the BMS to recover the battery.
-Press Soft Reset Button: Press the physical reset button for 10 seconds. Then the BMS will be reset to recover the battery. You can also activate the battery via the Bluetooth App directly.
Rest Button Picture
Store the battery correctly to avoid overdischarge. Follow the tips below:
–Physical Disconnection: Disconnect the battery from all the loads. Otherwise, the load will consume the battery to dead.
–SOC( State of Charge): Charge the battery to 50%-60% SOC before storage.
–Storage Environment: Store the battery at 10°C to 25°C, in a dry and clean warehouse away from fire.
–Maintenance: Check the battery voltage regularly every 6 months, and the main voltage should be around 13.1V-13.2V.
-Re-Activation: Fully charge the battery to 100% before use to reactivate the battery’s performance.
12V 20Ah LiFePO4 Off-Season Storage Checklist
| Category | Action Item | Target Specification |
| Charge Level | Set to 50% – 60% SOC | Voltage: 13.1V – 13.2V |
| Isolation | Disconnect Terminals | Physically remove (+) and (-) cables |
| Cleaning | Clean Terminals | Use a dry cloth (remove dust/corrosion) |
| Environment | Temperature Control | 10°C – 25°C (Cool & Dry) |
| Placement | Surface Protection | Store on a wooden shelf or non-metal surface |
| Safety | Physical Inspection | Check for cracks, swelling, or leaks |
| Maintenance | Quarterly Voltage Check | Set a reminder for every 90 days |
| Re-Activation | Pre-Season Full Charge | Charge to 100% before first use |
Unlike the lead-acid battery with only 50% usable energy and a rapid voltage drop, the Lifepo4 battery voltage curve is flat and steady at 12.8V-13.5V.
Voltage Curve:12V 20Ah LiFePO4 Vs Lead-Acid
| State of Charge (SOC) | LiFePO4 Voltage (Resting) | Lead-Acid Voltage (Resting) | The Difference |
| 100% (Full) | 13.4V – 13.6V | 12.7V – 12.8V | Lithium starts higher. |
| 70% | 13.2V | 12.4V | Lead-Acid has already dropped 0.4V. |
| 50% | 13.1V | 12.1V | Critical Point: Lithium is still “strong.” |
| 20% | 12.9V | 11.8V | Lead-Acid is struggling to power loads. |
| 10% (Empty) | 12.0V | 11.6V | Lithium drops off a “cliff” at the end. |
Both 12V 18Ah and 12V 20Ah are placed in the same-sized case.
A 12V 20Ah LiFePO4 battery is commonly used as a high-performance upgrade for a traditional 12V 18Ah lead acid battery. But they have slight differences in 2Ah capacity tolerance, 26Wh energy variance, 2A continuous discharge current tolerance, 4A peak discharge current, and 0.2Kg weight difference.
12V 18Ah Vs 12V 20Ah
| Feature | 12V 18Ah LiFePO4 | 12V 20Ah LiFePO4 |
| Nominal Capacity | 18 Amp-hours (Ah) | 20 Amp-hours (Ah) |
| Total Energy (Wh) | 230.4 Watt-hours | 256 Watt-hours |
| Standard Case Size | 181×77×167 mm (Commonly) | 181×77×167 mm (Commonly) |
| Max Continuous Discharge | Usually 18A (1C) | Usually 20A (1C) |
| Max Pulse Discharge | ~36A (for 1–3 seconds) | ~40A (for 1–3 seconds) |
| Standard Charge Current | 9A (0.5C) | 10A (0.5C) |
| Typical Weight | ~2.3 kg – 2.6 kg | ~2.5 kg – 2.8 kg |
| Usable Capacity | 100% (~18Ah) | 100% (~20Ah) |
12V 20Ah LiFePO4 battery pack is composed of 4 cells in a series configuration.
It’s critical to ensure all the 4 cells are in great consistency in 5mV voltage tolerance, 1mΩ internal resistance tolerance, and 10mAh capacity tolerance. When discharging a battery pack of cell inconsistency, the lower-voltage cell will reach the low-voltage protection to cut off the battery pack, while the other cells still have energy remaining. The battery pack can’t discharge the full capacity, which reduces the runtime. During charging, the higher-voltage cell will reach the high-voltage protection to cut off the battery pack, while the other cells are still not fully charged. The battery pack can’t be fully charged, which causes less electricity stored.
Critical Role of Cell Consistency in 20Ah LiFePO4 Packs
| Aspect | Why It’s Critical | Consequence of Poor Consistency |
| Safety | Prevents individual cells from being overcharged or over-discharged beyond safe voltage limits. | High risk of thermal runaway, fire, or swelling due to stressed “outlier” cells. |
| Capacity | The pack’s usable energy is dictated by the “Barrel Effect” (the weakest cell limits the chain). | Reduced runtime. A single 18Ah cell in a 20Ah pack wastes the potential energy of all other cells. |
| Performance | Ensures even current distribution and stable voltage levels during high-demand operation. | Significant voltage sag, power loss, and unexpected system shutdowns under load. |
| Lifespan | Allows all four cells in the series (4S) to age at the same rate as a cohesive unit. | Rapid degradation. The weakest cell works the hardest, failing far sooner than its rated cycle life. |
| BMS Function | Keeps cell voltages close together, allowing the BMS to balance efficiently during the final charge. | BMS Overload. The balancer cannot keep up, leading to permanent protection lockouts or failure. |
Yes.You can charge your 12V 20Ah lithium battery with the vehicle’s alternator.
But the alternator adopts the floating charge method with a constant 13.8V to 14.4V charge voltage, causing a high and unregulated current to damage the battery BMS. A dedicated lithium battery in DC to DC charging is recommended, which can protect the battery from overcharge and overdischarge to ensure ultimate safety.
Comparison: Direct vs. DC-to-DC Charging
| Feature | Vehicle Alternator (Direct) | Dedicated Lithium Charger (DC-to-DC) | The Conflict & Risk |
| Voltage | ~13.8V – 14.4V (Fluctuates) | Precise 14.2V – 14.6V | Fluctuations can leave lithium cells undercharged or cause stress. |
| Current | Unregulated & High (60A – 150A+) | Regulated (e.g., 10A for a 20Ah pack) | A 20Ah battery will try to pull more current than it can handle, causing overheating. |
| Charge Stage | Float/Maintenance only (Single stage) | CC/CV with Full Cutoff | No cutoff! The alternator may overcharge the lithium, a major safety hazard. |
| BMS Sync | None. No communication. | Designed to work with Lithium BMS. | If the BMS shuts off, the alternator sees an “open circuit,” causing voltage spikes that can fry vehicle electronics. |
| Efficiency | Poor (Often hits only 80% charge) | 95%+ (Ensures 100% Full Charge) | Alternators aren’t designed to “top off” the flat lithium voltage curve. |
