Asus B21N1818-3 Original Laptop Battery For Asus A409UJ D409DA F509UA K509FA P1503DA

4,299.005,299.00 Incl GST (-39%)

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  • Condition: Brand New
  • Voltage: 7.6 V – Capacity: 32Wh 4212mAh
  • Number of Cells: 2 cells
  • Cell Type: Li-Polymer , Color: Black
  • Compatible with Asus A409UJ D409DA F509UA K509FA P1503DA
  • Warranty: 6 Months & 12months Replacement warranty Lap Gadgets (30 days money back guarantee)
  • NOTE:- Please Select Warranty from the given option Menu
  • Reach our product expert at +91-261-3510304 for more information.
6 Months Warranty12 Months Warranty
👨‍👨‍👦‍👦-Someone from Bangalore Rural & 4 others bought this item recently.

Real Reviews on Google.

Genuine products.
Ajay Anand
Ajay Anand
Good website store for laptop parts..good delivery in north india
Maneesh Pathak
Maneesh Pathak
I received well packed and very well working bettery. Initially i am worried about company ,since its first time i have chosen,and get very well communication on watup . Another thing about product I have received manufacturing of 2019,but as i attach my laptop and review two days , I can say its awesome. Thanking you Lap Gadgets team. I also give my opinion ,for better for people like me ,if your application like other ecommerce platform,it will be more interactive for us. But overall i can say its trustable and reliable. Thanks
Mohan Kakumanu
Mohan Kakumanu
I have purchased a laptop battery and I was having trouble in replacement and the support helped me by doing video call and explaining.
Manideep Dhar
Manideep Dhar
The urge to write about my experiences with LapGadgets made me ask for the review link from them. It would be difficult to comprehend my experience in words though but still for the benefit of customers like me I would. It so happened that my ThinkPad’s battery had died and I purchased a new battery about a year ago from LapGadgets, which they supplied was original and due to perhaps several charging cycles it’s capacity dipped to a significant fraction and since LapGadgets offered 1 year warranty with the same I reached out to them to which they promptly responded. I must mention Mr. Jignesh from LapGadgets who took an extra mile to send me a fresh, original and obviously non-refurbished battery pack within promised time, the experience between these was amazing and I would always recommend LapGadgets for everyone to fulfil their laptop parts replacements
Manan Badala
Manan Badala
I ordered multiple macbook usb c compatible chargers , quality was superb , Jignesh bhai provided me discounts , next day delivery, nice packing, overall nice experience , would easily recommend to anyone buying compatible chargers
Shamsher Singh
Shamsher Singh
I had a wonderful experience with Lap Gadgets . I received the Laptop Battery which was, unfortunately not the right one for my HP laptop. Before I reached the concerned personnel , I doughts for replacement. However, to my surprise , the matter was resolved immediately on priority. I am thankful to them and I wish to place it on record. Shamsher Singh.
akiL Totanawala
akiL Totanawala
I placed an Order for my Laptop & it was delivered in 3 days .. The Battery is Genuine & comes with One Year Warranty ..

Asus battery with logo

Product Description

Lap Gadgets batteries keep you connected always to carry out your important work on your laptop. No matter wherever you are.

Our replacement batteries are best in market in terms of quality, reliability and price. You are being asssured for every paise you spent on our batteries.

  • Fresh batteries – 0-Cycle – all our batteries are unused, fresh directly from factory.
  • Premium Cells – We use quailty cells with atmost capacity.
  • Rigorous Testing – All our batteries are tested to ensure it gives optimal performance to you.

Product highlights

  • Type – Lithium-ion battery
  • Cells –  2 cells 
  • Capacity – 4212 mAh


  • 6 months & 12 months carry in replacement warranty 

Return & Replacement

  • We are confident in our product hence we give you 10 days free returns & 30 days self return window to either get replacement or return (know more)

High Quality Asus B21N1818 battery

High quality component

This Asus B21N1818 battery replacement has built-in A+ grade cells and high-quality TI intelligent control chip, which not only performs better, charges faster but lasts longer. In addition, the outer shell of the Asus B21N1818 battery is made according to the original battery shape design scheme, using high temperature and wear-resistant ABS +PC alloy environmentally friendly materials, which can be 100% compatible with your laptop and fit closely.

100% True Capacity

Do not be deceived by the false capacity advertisements from bad merchants, of which battery capacity will often drop off significantly after using a few months. Made with the highest quality “A” grade cells, our Asus B21N1818 laptop battery has passed various strict quality tests to ensure that it meets OEM specifications, which can provide more than 600 charging cycles to maintain the same capacity for a long time.

Safety first!

Using a poor battery with unstable performance may do harm to the notebook and your safety. Our Asus B21N1818 replacement battery has passed CE, UL, ROHS, and other international authority certifications, which provides a variety of protection functions, effectively preventing common risks such as short circuits, overheating, and overvoltage. In order to protect your laptop and your safety, please rest assured to purchase our high-quality batteries!

Why buy from Lap Gadgets ?

Fast Shipping

The shipment will be arranged within 24 hours (working day) after we receiving the order. The shipping notification will be sent via email after confirming the shipment, which will contain the details of your order and tracking information of the package.

Secure Packaging

To ensure that the new Asus B21N1818 battery can be safely delivered to your hands, it will be firstly packed in an anti-static bag, then wrapped with a drop-proof synthetic foam, finally enclosed into sturdy cardboard and sealed with waterproof plastic tape

30 Days Money Back

In order to minimize the risk during the purchase process from customers, our return period is 30 days instead of 7 or 14 days! You can easily request a refund within 30 days since receiving the product if you are not satisfied with our Asus B21N1818 laptop battery or our service.

10 days Free Repair/Replacement

Now get hassle free return / replacement within 10 days of delivery to you. In case of issue in the item purchased inform us within 10 days of delivery, we will arrnage free pickup for returns or replacement.

Safety first

Over Voltage Protection
Over Charge Protection
Over Discharge Protection
Electromagnetic Protection
Over Heating Protection
Short Circuit Protection
Intelligent Protection
Charging Time Protection

Compatible Part Numbers

  • 0B200-03450000
  • B21N1818-1
  • B21N1818-2
  • B21N1818-3
  • C21N1818-2
  • C21N1818-1
  • C21N1818-3

Fits Laptop Models

  • A409FA
  • A409FB
  • A409FJ
  • A409FL
  • A509FA
  • A509FA-EJ145T
  • A509FA-EJ146T
  • A509FA-EJ178T
  • A509FA-EJ211T
  • A509FA-EJ253T
  • A509FB
  • A509FJ
  • A509FL
  • F409FA
  • F409FB
  • F409FL
  • F509FA
  • F509FA-EJ207T
  • F509FB
  • F509FB-EJ117T
  • F509FB-EJ118T
  • F509FJ
  • F509FL
  • FL8700FB
  • FL8700FJ
  • FL8700FL
  • Laptop 15 X509JA
  • Laptop 15 X509JA-BQ040T
  • Laptop 15 X509UA
  • Laptop 15 X509UB
  • Laptop 15 X509UJ
  • M509DA
  • M509DA-EJ153T
  • R427FA
  • R427FB
  • R427FJ
  • R427FL
  • R521FA
  • R521FA-EJ111T
  • R521FA-EJ112T
  • R521FB
  • R521FJ
  • R521FL
  • VivoBook 14 X409FA-BV012AT
  • VivoBook 14 X409FA-EK034T
  • VivoBook 14 X409FA-EK041T
  • VivoBook 14 X409FA-EK070T
  • VivoBook 14 X409FA-EK098T
  • VivoBook 14 X409FA-EK099T
  • VivoBook 14 X409FA-EK149T
  • VivoBook 14 X409FA-EK199T
  • VivoBook 14 X409FA-EK502T
  • VivoBook 14 X409FA-EK555T
  • VivoBook 14 X409UA
  • VivoBook 14 X409UA-BV050T
  • VivoBook 14 X409UA-BV074T
  • VivoBook 14 X409UA-BV105T
  • VivoBook 14 X409UA-BV111T
  • VivoBook 14 X409UA-EB053T
  • VivoBook 14 X409UA-EK035T
  • VivoBook 14 X409UA-EK036T
  • VivoBook 14 X409UA-EK054T
  • VivoBook 14 X409UA-EK080T
  • VivoBook 14 X409UA-EK092T
  • VivoBook 14 X409UA-EK093T
  • VivoBook 14 X409UA-EK341T
  • VivoBook 14 X409UA-EK342T
  • VivoBook 14 X409UA-EK361TS
  • VivoBook 14 X409UA-EK362TS
  • VivoBook 14 X409UA-HT071T
  • VivoBook 15 F509FA
  • VivoBook 15 F509FA-EJ014T
  • VivoBook 15 F509FA-EJ207
  • VivoBook 15 F509FA-EJ255T
  • VivoBook 15 F509FA-EJ337
  • VivoBook 15 F509FA-EJ337T
  • VivoBook 15 F509FA-EJ501T
  • VivoBook 15 F509FA-EJ551
  • VivoBook 15 F509FA-EJ672T
  • VivoBook 15 M509DA
  • VivoBook 15 M509DA-BQ206
  • VivoBook 15 M509DA-BQ321T
  • VivoBook 15 M509DA-BR123T
  • VivoBook 15 M509DA-BR132T
  • VivoBook 15 M509DA-BR139T
  • VivoBook 15 M509DA-BR151
  • VivoBook 15 M509DA-BR155T
  • VivoBook 15 M509DA-BR218
  • VivoBook 15 M509DA-BR241
  • VivoBook 15 M509DA-BR260
  • VivoBook 15 M509DA-BR290T
  • VivoBook 15 M509DA-EJ024T
  • VivoBook 15 M509DA-EJ025T
  • VivoBook 15 M509DA-EJ034T
  • VivoBook 15 M509DA-EJ043
  • VivoBook 15 M509DA-EJ051T
  • VivoBook 15 M509DA-EJ058T
  • VivoBook 15 M509DA-EJ068
  • VivoBook 15 M509DA-EJ068T
  • VivoBook 15 M509DA-EJ072T
  • VivoBook 15 M509DA-EJ073T
  • VivoBook 15 M509DA-EJ084T
  • VivoBook 15 M509DA-EJ085T
  • VivoBook 15 M509DA-EJ098T
  • VivoBook 15 M509DA-EJ102T
  • VivoBook 15 M509DA-EJ126T
  • VivoBook 15 M509DA-EJ153T
  • VivoBook 15 M509DA-EJ156T
  • VivoBook 15 M509DA-EJ176T
  • VivoBook 15 M509DA-EJ194T
  • VivoBook 15 M509DA-EJ292T
  • VivoBook 15 M509DA-EJ333T
  • VivoBook 15 M509DA-EJ443T
  • VivoBook 15 M509DA-EJ541T
  • VivoBook 15 M509DA-EJ561T
  • VivoBook 15 M509DA-EJ562T
  • VivoBook 15 M509DA-EJ581T
  • VivoBook 15 M509DA-EJ582T
  • VivoBook 15 M509DA-EJ641T
  • VivoBook 15 M509DA-EJ94T
  • VivoBook 15 M509DA-EJ95T
  • VivoBook 15 M509DA-WB302
  • VivoBook 15 M509DA-WB331
  • VivoBook 15 M509DA-WB332
  • VivoBook 15 M509DA-WB502
  • VivoBook 15 M509DA-WB712
  • VivoBook 15 M509DA-WB712T
  • VivoBook 15 X509UA
  • VivoBook 15 X509UA-EJ001T
  • VivoBook 15 X509UA-EJ021T
  • VivoBook 15 X509UA-EJ050T
  • VivoBook 15 X509UA-EJ062T
  • VivoBook 15 X509UA-EJ064T
  • VivoBook 15 X509UA-EJ071T
  • VivoBook 15 X509UA-EJ073T
  • VivoBook 15 X509UB
  • VivoBook 15 X509UB-BR061T
  • VivoBook 15 X509UB-EJ009T
  • VivoBook 15 X509UB-EJ010T
  • VivoBook 15 X509UB-EJ021T
  • VivoBook 15 X509UJ
  • VivoBook 15 X509UJ-BR044T
  • VivoBook 15 X509UJ-EJ036T
  • VivoBook 15 X509UJ-EJ048T
  • VivoBook 15 X545FA
  • VivoBook 15 X545FA-EJ085T
  • VivoBook 15 X545FA-EJ116T
  • VivoBook 15 X545FJ
  • VivoBook 15 X545FJ-BQ034T
  • VivoBook 15 X545FJ-EJ009T
  • VivoBook 15 X545FJ-EJ064T
  • VivoBook 15 X545FJ-EJ065T
  • VivoBook F509FA-EJ255T
  • X409FA
  • X409FB
  • X409FL
  • X509FA
  • X509FA-BR030T
  • X509FA-BR032T
  • X509FA-DB51
  • X509FA-DB71
  • X509FA-EJ099T
  • X509FA-EJ101T
  • X509FA-EJ103T
  • X509FB
  • X509FB-EJ024
  • X509FJ
  • X509FJ-0111G8265U
  • X509FJ-0131S8265U
  • X509FJ-AP8205T
  • X509FJ-BR012T
  • X509FJ-BR013T
  • X509FJ-EJ014
  • X509FJ-EJ049T
  • X509FJ-EJ051T
  • X509FJ-EJ053T
  • X509FJ-EJ055T
  • X509FJ-EJ115T
  • X509FJ-EJ121T
  • X509FJ-EJ139T
  • X509FJ-EJ145T
  • X509FJ-EJ155T
  • X509FJ-EJ501T
  • X509FJ-EJ701T
  • X509FL
  • X509JA
  • X509JA-BQ039T
  • X509JA-BQ084T
  • X509JA-BR072T
  • X509JA-BR104T
  • X509JA-BR131T
  • X509JA-EJ024T
  • X509JA-EJ025T
  • X509JA-EJ026T
  • X509JA-EJ027T
  • X509JA-EJ028T
  • X509JA-EJ031T
  • X509JA-EJ105T
  • X509JA-EJ107T
  • X509JA-EJ114T
  • X509JA-EJ129T-BE
  • X509JA-EJ140T
  • X509JA-EJ141T
  • X509JA-EJ147R
  • X509JA-WB501T
  • X509UA
  • X509UA-BR011T
  • X509UA-BR035T
  • X509UA-BR036T
  • X509UA-BR112T
  • X509UA-BR113T
  • X509UA-BR236T
  • X509UA-EJ009T
  • X509UA-EJ050T
  • X509UA-EJ061T
  • X509UA-EJ062T
  • X509UA-EJ064T
  • X509UA-EJ071T
  • X509UA-EJ073T
  • X509UA-EJ103T
  • X509UB
  • X509UB-EJ009T
  • X509UB-EJ010T
  • X509UB-EJ021T
  • X509UJ
  • X509UJ-BQ022T
  • Y4200FA
  • Y4200FB
  • Y4200FJ
  • Y4200FL
  • Y5200
  • Y5200FA
  • Y5200FB
  • Y5200FJ
  • Y5200FL

Some tips to increase the life of Asus B21N1818 battery

  1. Please carefully read the instructions before using the battery.
  2. Before using the new replacement Asus B21N1818 for the first time, make sure that the battery is full charge for the first time usage and then get it discharge up to 5% and then recharge it for the same pattern for couple of times.
  3. You’d better use a dedicated AC adapter when charging the new Asus B21N1818 battery
  4. You’d better turn off your Asus laptop when the Asus B21N1818 battery is charging; do not pull out the power plug or use your computer when charging for the first time.
  5. If you don’t use laptop for a long time, please remove the Asus B21N1818 battery, and place it in a ventilated and dry place.
  6. Excessively high or low temperature environment should be avoided when using the replacement Asus B21N1818 battery, as the too low or too high temperature will affect the battery life.

Additional information

Weight N/A
Dimensions N/A

6 months, 12 months


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Q & A

Will it fit for ASUS Vivobook 15 M509DA-BQ1063T Tharun asked on November 24, 2022

yes it is compatible with your given model number

sandip201091 answered on November 24, 2022
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b21n1818 b21n1818-1

Asus B21N1818-3 Original Laptop Battery For Asus A409UJ D409DA F509UA K509FA P1503DA

4,299.005,299.00 Incl GST (-39%)

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Buy with confidence with our No RISK purchase. We offer 10 days free returns and 30 days moneyback guarantee in our products (click here) to know more.

Warranty Terms:

Hello and welcome to our store! We are committed to providing the best service possible and want to ensure that you have the most up-to-date information on our product warranties. Rest assured that all of our products come with a warranty specific to their particular model. We encourage you to take a moment to check the product description or specification before completing your purchase, so that you are aware of the specific warranty offered for your item. 

For example, we want you to know that for laptop batteries, we provide a 6-month or 12-month warranty, depending on the product. As for laptop chargers, the warranty period is 12 months. We hope that this information is helpful to you and that you can shop with confidence, knowing that we stand behind the quality of our products and are ready to assist you with any questions or concerns you may have.

Your safety is our highest priority:

We use industry best tools to protect your valuable data and privacy. Our payment security system encrypts your information throughout transmission. We never share your credit card details with any third-party vendors, and we don’t sell your information to others. 


Why you should buy from us ?

Lap Gadgets is a certified Dell Sales Affiliate with code: GJ1AAE 


First 100 customer offer


in installation charges.


Easy Returns

Buy with confidence with our No RISK purchase. We offer 10 days free returns and 30 days moneyback guarantee in our products (click here) to know more.

f you aren’t 100% satisfied with this item you may return it or exchange it for free within 10 days after delivery. Simply bring it back to our store or mail it back to us with a free, pre-paid return label. After 10 days no free return eligible, you can still either self return or pay the return courier charges. 

I need to return an item.
Need help now? Let’s chat on whatsapp


Buy with confidence with our No RISK purchase. We offer 10 days free returns and 30 days moneyback guarantee in our products (click here) to know more.

Easy Returns
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Free shipping across nation for selected products. Shop at with confidence by mode of Cash on delivery / credit / debit card in selected cities. With more than 26000 pin code covered in India.

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Best in class customer support. We consider your issues as ours. We are available on call (0261-3510304) or watsapp (click here) or mail us your query at [email protected] Timings are 10:30 am to 6.30 pm 

Get experts advice in buying correct laptop parts. Avoid the risk of laptop failure and other damage which may occur due to wrong part purchase. Our experts will be happy assisting you.

Expert's Advice

Online. In store. Always free.

If you aren’t 100% satisfied with this item you may return it or exchange it for free within 10 days after delivery. Simply bring it back to our store or mail it back to us with a free, pre-paid return label. After 10 days no free return eligible, you can still either self return or pay the return courier charges. 

I need to return an item.

Need help now? Let’s chat on whatsapp.