20A Smart Battery Charger & Maintainer 12V/24V, 9-Stage, Lithium Capable, Multi-Amp, Fan Cooled with Repair Mode
Delivery and Shipping
Delivery and Shipping
- Shipping is a flat rate of $11.99, *however occasionally Heavy or Bulky items, Dangerous Goods or deliveries to regional/remote areas may incur an extra freight charge. Our Customer Service team will be in contact if this does occur.
- Orders to major capital cities except WA generally arrive within 3 to 5 business days, WA delivery times are normally 5 to 10 business days.
- For further information please refer our Shipping & Delivery page.
365-Day Warranty
365-Day Warranty
- AutoMegaStore offers a 365-day warranty - 365 days from date of purchase. We will either credit, replace, or refund your item. The warranty covers all manufacturing faults and defects.
- For further information please refer our Warranty page.
Item Returns
Item Returns
- At AutoMegaStore, we want you to be 100% happy with your purchase. If, for any reason, you are not satisfied, you may return the product to us within 30 days of the date of purchase.
- Email us with your name, order number, and images of the intended returned product, and our Customer
Care team will arrange authorisation for the return. - For further information please refer our Refunds & Returns page.

Stay Fully Charged with This 20A Smart Battery Charger - Built for Big & Small
From mowers to mining trucks, this smart batter charger is the best 12V/24V for high-demand jobs. Select between 5 Amp, 10 Amp, and 20 Amp outputs, inbuilt with intelligent 9-stage charging, and lithium-ready teachnology, this unit charges faster, runs cooler, and works smarter than any other on the market.
- Multi-Amp Output (5A / 10A / 20A): Adjust to suit battery size randing from 10AH to 600AH for safe, fast charging
- 12V & 24V Auto Detection: No buttons- just plug and play
- Lithium Capable: Fully compatible with Lithium PifePO4, BMS, AGM, GEL, SLA, Flooded, and Deep Cycle Batteries
- Repair Mode: Revives flat or sulphated Lead Acid batteries
- Fan-Cooled + Temp Compensated: Prevents overheating and keep this charger working for years to come
- Built-In Battery Management: Float, Trickle, and Reconditioning stages protect and maintain battery health for the long-term
- Full Safety Features: Over-voltage, reverse polarity, over-current, low voltage, and short circuit protection built-in
- 9-Stage Charging Process: Desulfation → Soft Start → Bulk → Absorption → Trickle → Test → Recondition → Float → Maintenance
The best Smart Battery Charger for trucks, buses, 4WD's, vans, campervans, sedans, tractors, mowers, motorbikes, caravans, boats, farm machinery, golf carts & more...
Inside every box expect a 20A Smart Battery Charger & Maintainer, clamp extension, eye terminal extension, two additional eyelets, 240V plug & lead, and a user manual - all packed and ready to go.
Model | AMS40840 |
Voltage | 12V / 24V (Auto Detect) |
Output Options | 5A / 10A / 20A |
Battery Capacity | 10AH to 600AH |
Supported Battery Types | AGM, SLA, GEL, Flooded, Deep Cycle, EFB, Lithium (BMS, LifePO4) |
9-Stage Charging | Desulfation, Soft Start, Bulk, Absorption, Trickle, Test, Recondition, Float, Maintenance |
Minimum Starting Voltage | 7 Volts |
Cooling | Built-in fan |
Safety Protections | Over-voltage, Over-current, Over-heating, Short circuit, Reverse polarity |
Dimensions | 157.5mm (L) x 88.5mm (W) x 51mm (H) |
Warranty | 24 Months |
Payment & Security
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