The Amazon Basics 20000mAh Power Bank (model ABPB78) is a 20,000mAh lithium polymer power bank with a USB-C port rated up to 35W, a USB-A port and a digital percentage display. For most buyers it is a high-capacity everyday and travel power bank for phones, earbuds and tablets, with the 35W USB-C output as its main selling point. The catch is that the listing leaves out several details that matter, such as the recharge (input) speed and the exact fast-charging standards supported.
Amazon Basics does not publish a separate specification page for this model, so the Amazon.in listing is the main source here. Everything below is based on that listing, as captured on 17 October 2026, and on general charging knowledge. We have not tested this power bank, and we could not find an independent review of this specific model to cite.
The Amazon link in this article is for the White version titled “Amazon Basics 20000mAh Power Bank, 35W Super Fast Charging, Type-C and USB-A Ports, 9-Layer Protection, Portable, White”. Check the colour on the listing before ordering, because one field in the listing’s technical details describes the colour differently.
Quick verdict
- Best for: phone users who want roughly two full charges on trips, and owners of phones or tablets that accept USB-C fast charging
- Skip if: you want to charge a laptop properly, need wireless or magnetic charging, or want published recharge times
- Key strengths: 20,000mAh capacity, up to 35W from USB-C, USB-C and USB-A ports, digital percentage display, 9-layer protection claim, made in India
- Key limitations: input wattage, fast-charging protocols and per-port USB-A output are not stated, the warranty is 6 months, and some listing fields contradict each other
| Specification | Amazon Basics 20000mAh 35W (Amazon.in listing) |
|---|---|
| Model number | ABPB78 |
| Capacity | 20,000mAh |
| Battery type | Lithium polymer |
| Maximum output | Up to 35W from the USB-C port |
| Ports | USB-C and USB-A (technical details list 3 ports) |
| Display | Digital battery percentage display |
| Protection | 9-layer circuit protection (as claimed) |
| Dimensions | About 11.4 x 7.2-7.3 x 3-3.1 cm (two listing fields differ slightly) |
| Weight | About 319-320 g |
| In the box | Power bank, USB cable, user manual, warranty card |
| Warranty | 6 months |
| Manufacturer | Veeflex Electrikals Private Limited |
| Country of origin | India |
Check the current price of the Amazon Basics 20000mAh 35W Power Bank (White) on Amazon.in
How many charges can 20,000mAh really give?
The Amazon.in listing says the power bank delivers up to two full charges for most smartphones. That claim is reasonable on paper, and it helps to understand why a 20,000mAh power bank does not give four charges to a 5,000mAh phone.
The 20,000mAh figure refers to the internal cells at their own voltage, which for lithium cells is usually around 3.6V to 3.7V. To charge a phone over USB, the power bank must convert that to 5V or higher, and some energy is lost as heat in the power bank, the cable and the phone. Real-world delivered energy from any power bank is therefore noticeably lower than the label suggests. As a rule of thumb, a 20,000mAh unit typically delivers something like two charges for a phone with a 4,500mAh to 5,000mAh battery, which matches the listing’s claim. This is a general estimate, not a test result for this model.
Tablets with large batteries will get roughly one charge or a little more. Earbuds and smartwatches will get many top-ups, but small devices sometimes draw so little current that a power bank may switch itself off early. Many power banks offer a low-current mode for this, but the listing does not mention one, so check the user manual if you charge earbuds or a smartwatch often.
What the 35W USB-C output means for your phone
The listing rates the USB-C port at up to 35W. That is more than most phones actually request, so for many people the practical benefit is that the port is unlikely to be the bottleneck. A phone only charges as fast as both sides agree on, and that agreement depends on the charging standard.
Here the listing is vague. It says “35W super fast charging” but does not name USB Power Delivery (PD), Programmable Power Supply (PPS) or Quick Charge. iPhones from the iPhone 8 onwards fast-charge over USB PD, while Samsung’s “Super Fast Charging” relies on PD with PPS. Without the protocol details, we cannot confirm which phones will reach their fastest mode, so treat the 35W figure as a ceiling, not a promise for your handset.
Laptops are another question. The listing mentions smartphones, tablets and “more” but does not claim laptop support. A 35W USB-C output may keep a low-power USB-C laptop topped up or charge it slowly when it is idle, but it is not a replacement for a 45W or 65W laptop charger.
What the listing leaves unclear
Several fields in the Amazon.in listing are incomplete or inconsistent. None of these is a reason to avoid the product on its own, but you should know about them before buying.
- Recharge speed: the input wattage and recharge time are not stated. A 20,000mAh battery recharged slowly can take most of a night, so if you need fast turnaround, this is the biggest unknown.
- Port count: the title mentions a Type-C port and a USB-A port, while the technical details say three ports. The listing images are the best way to see the exact port layout.
- Built-in cable: one technical field lists “Built In Cable” as a feature, but the included components list a separate USB cable. Check the images to see whether there is a cable attached to the body.
- Colour: the title says White, while a technical field says “Wired – Silver”. Confirm the colour shown in the listing images for this ASIN.
- Per-port output: only the USB-C maximum (35W) is stated. The USB-A output and the combined output when both ports are used are not published.
Design, display and safety
According to the listing, the power bank has a matte finish and measures about 11.4 cm long, 7.2 to 7.3 cm wide and 3 to 3.1 cm thick, with a weight of roughly 319 to 320 g. That is normal for a 20,000mAh unit: it fits a bag or a jacket pocket, but it is heavier than a phone and not something you will forget you are carrying.
The digital percentage display is genuinely useful. Four-LED indicators on cheaper power banks only tell you the charge in 25% steps, while a percentage readout makes it easier to decide whether you can leave home without recharging.
The listing claims 9-layer circuit protection but does not name the individual protections. Common protections in power banks include overcharge, over-discharge, over-current, short-circuit and temperature control. Do not assume any specific protection beyond what the listing states, and follow basic battery care regardless.
Flying with a 20,000mAh power bank
Power banks must normally travel in cabin baggage, not checked luggage, and airlines limit them by watt-hours (Wh). The listing does not print a watt-hour rating. At a typical 3.6V to 3.7V cell voltage, 20,000mAh works out to roughly 72Wh to 74Wh, which is below the 100Wh level that many airlines use as the limit for carrying power banks without approval. Always check the rating printed on the unit itself and your airline’s current rules before flying, as some airlines have tightened power bank rules.
Who should buy it, and who should not
- Buy it if you want a high-capacity power bank for travel, long commutes or power cuts, mostly for phones and earbuds.
- Buy it if you like seeing an exact battery percentage and want both USB-C and USB-A outputs.
- Skip it if you need confirmed PPS support for Samsung Super Fast Charging, or a published recharge time.
- Skip it if you want wireless or magnetic charging, or regular laptop charging.
- Skip it if a 6-month warranty feels too short for a battery product you plan to use daily.
Alternatives worth comparing
These Ambrane models publish their specifications on Ambrane India’s official site, checked on 17 October 2026.
- Ambrane Stellar 20K: a 20,000mAh semi-solid power bank with up to 22.5W output, one USB-C and one USB-A port, a detachable USB-C to USB-C loop cable and LED charge indicators instead of a screen. Lower peak output, but clearer specifications.
- Ambrane AerosynQ Orbit 20K: a 20,000mAh power bank with up to 35W wired output over USB-C, 25W Qi2 wireless charging, one USB-A port and two Type-C connections, one of which is a built-in cable. Better if you use a MagSafe-compatible iPhone.
- Ambrane PowerlitDuo 30: a 20,000mAh, 33W power bank with two USB-C ports that work for input and output plus a USB-A port rated up to 22.5W. Read our Ambrane PowerlitDuo 30 review for details.
Buying checklist
- Confirm the listing title says 20000mAh, 35W, Type-C and USB-A, and White, and that the model number is ABPB78.
- Check the listing images for the exact port layout and whether there is a built-in cable.
- Use a USB-C cable that supports your phone’s fast-charging standard. A basic cable can limit speed.
- Keep the invoice and warranty card. The listing states a 6-month warranty, and the manufacturer is Veeflex Electrikals Private Limited.
- On delivery, check that the display works and that the unit charges your phone from both ports before the return window closes.
- For help choosing wattage across phones and laptops, see our power bank and charger buying guide.
See the White Amazon Basics 20000mAh 35W Power Bank on Amazon.in
Battery care tips
- Avoid leaving the power bank in a parked car or direct sun, where heat speeds up battery ageing.
- Recharge it every few weeks if you store it, because lithium cells should not sit fully empty for long.
- Stop using it if it swells, gets unusually hot, or smells of burning, and contact support.
- Do not cover it with a pillow or blanket while it charges a device.
Frequently asked questions
How many times can the Amazon Basics 20000mAh power bank charge a phone?
The Amazon.in listing claims up to two full charges for most smartphones. The actual number depends on your phone’s battery size and conversion losses.
Does it support 35W charging on both ports?
The listing rates only the USB-C port at up to 35W. The USB-A output is not stated.
Will it fast-charge a Samsung Galaxy or an iPhone?
The listing does not name the fast-charging protocols. iPhones fast-charge over USB PD and Samsung Super Fast Charging needs PD with PPS, so their top speed cannot be confirmed from the listing.
How long does it take to recharge?
The listing does not state the input wattage or the recharge time, so we cannot give a figure.
What is the warranty?
The listing states a 6-month warranty, and a warranty card is listed among the box contents.
Bottom line
The Amazon Basics 20000mAh 35W Power Bank (ABPB78) offers the core things most buyers want: big capacity, a USB-C port rated up to 35W, a USB-A port and an exact percentage display. The listing’s gaps on recharge speed, protocols and port layout mean it is best for buyers who mainly need dependable phone top-ups rather than confirmed peak speeds. If that matches your use, it is worth a look.
Check the current price of the Amazon Basics 20000mAh Power Bank on Amazon.in
Related reading on GadgetSoch: Ambrane Charge i45 Review: 45W GaN Type-C Charger for Phones and Laptops, Explained and Xiaomi Power Bank 4i 20000mAh 33W Review: Ports, Charging Speeds and Limits.
Sources
- Amazon.in listing for ASIN B0F53KGSFZ, Amazon Basics 20000mAh Power Bank ABPB78 (title, feature bullets and technical details; captured 17 October 2026)
- Ambrane India: Stellar 20K (checked 17 October 2026)
- Ambrane India: AerosynQ Orbit 20K (checked 17 October 2026)
- Ambrane India: PowerlitDuo 30 (checked 17 October 2026)
