{"product_id":"galaxy-s21-battery-case-4800mah","title":"Galaxy S21 Battery Case 4800mAh – Extended Power Charger","description":"\u003ch3\u003eDouble Your Galaxy S21 Battery Without Carrying Anything Extra\u003c\/h3\u003e\n\u003cp\u003eThe Galaxy S21 is still a brilliant phone — compact 6.2-inch display, flagship camera, smooth performance. Its one aging weakness is the battery. A 4000mAh cell that was merely adequate at launch now struggles through a modern day of streaming, navigation, and hotspotting. This Galaxy S21 Battery Case solves it the smart way: a built-in 4800mAh lithium-ion pack wrapped inside a slim protective case, adding 100% extra juice — that is up to 14 hours more talk time, 15 hours of filming, or 56 hours of music — while guarding your phone with 360-degree protection. It is engineered exclusively for the Galaxy S21 (6.2 inch); it will not fit the S21+ or S21 Ultra. One case, two jobs, zero dead-battery panic.\u003c\/p\u003e\n\u003ch3\u003e10 Key Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e4800mAh Built-In Battery\u003c\/strong\u003e – A high-efficiency Li-ion pack that effectively doubles the S21's stock 4000mAh battery — 100% extra juice on demand.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e2-in-1 Charge + Protect\u003c\/strong\u003e – Power bank and protective case fused into one, so you never juggle a separate brick and cable.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eOne-Click Power Control\u003c\/strong\u003e – Press the integrated power button once to start charging, twice to stop — you decide exactly when to spend your reserve.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e4-Light LED Power Gauge\u003c\/strong\u003e – Each LED represents 25% of remaining case battery, so you always know what is left in the tank.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSimultaneous Pass-Through Charging\u003c\/strong\u003e – Plug in one cable and both the phone and the case charge together, stopping automatically when full.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003e360° Full-Body Protection\u003c\/strong\u003e – Reinforced corners, covered sides, and a protective back shield the phone from bumps, scratches, and dust.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdvanced Silicone Side Walls\u003c\/strong\u003e – Soft-touch silicone edges add grip and shock absorption where drops actually land.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSmart Safety Circuitry\u003c\/strong\u003e – Built-in short-circuit and overcharge protection guard both batteries on every charge.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNo-Chin Slim Design\u003c\/strong\u003e – Precise cutouts keep every button, port, and the camera fully accessible, with no bulky chin below the screen.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTravel-Legal Capacity\u003c\/strong\u003e – At roughly 17.8Wh, it is far below the 100Wh FAA carry-on limit — fly with it anywhere.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eMaterials \u0026amp; Specifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eBattery:\u003c\/strong\u003e 4800mAh lithium-ion (approximately 17.8Wh), high conversion efficiency\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdded battery life:\u003c\/strong\u003e up to 14 hours talk, 15 hours filming, 56 hours music\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBuild:\u003c\/strong\u003e hard plastic shell with advanced silicone side protection\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e approximately 120 g \/ 4.2 oz (estimated)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdded thickness:\u003c\/strong\u003e approximately 5–6 mm at the back (estimated)\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIndicator:\u003c\/strong\u003e 4-light LED gauge, 25% per light\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCharging input:\u003c\/strong\u003e USB-C — use the original Samsung charger and cable for best results\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSafety:\u003c\/strong\u003e short-circuit and overcharge protection\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompatibility:\u003c\/strong\u003e Samsung Galaxy S21 5G (6.2 inch) ONLY — not S21+ or S21 Ultra\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eNot supported while in case:\u003c\/strong\u003e wireless charging, Samsung Pay, Android Auto, Quick Charge, USB-C wired headphones, PC data sync\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eProtecting a different Samsung? Browse the complete \u003ca href=\"https:\/\/gorillacasestore.com\/collections\/samsung-cases\"\u003eGorilla Cases Samsung Cases collection\u003c\/a\u003e for every Galaxy model we cover.\u003c\/p\u003e\n\u003ch3\u003e5 Real-World Use Cases\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe Field Technician\u003c\/strong\u003e – On job sites from 7 a.m. with the phone running diagnostics and photos all day, the double battery means the van charger becomes optional.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe Long-Haul Traveler\u003c\/strong\u003e – Airport days devour batteries. With 17.8Wh of carry-on-legal reserve strapped to the phone, boarding passes never go dark.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe Delivery Driver\u003c\/strong\u003e – GPS on screen for eight straight hours is the hardest battery test there is. This case turns the S21 into a two-shift phone.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe Festival Parent\u003c\/strong\u003e – All-day events with kids mean photos, videos, and locating texts. The one-click reserve keeps the family hub online until the fireworks.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThe Budget Maximizer\u003c\/strong\u003e – Keeping the S21 another two years instead of upgrading? Doubling its daily endurance is the single best dollar-per-day move you can make.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eFeatures \u0026amp; Benefits at a Glance\u003c\/h3\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003cth\u003eFeature\u003c\/th\u003e\n\u003cth\u003eBenefit\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4800mAh built-in pack\u003c\/td\u003e\n\u003ctd\u003eAdds 100% extra battery — a true second day of use\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOne-click power button\u003c\/td\u003e\n\u003ctd\u003eYou control when reserve power is spent\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4-LED gauge\u003c\/td\u003e\n\u003ctd\u003eReserve level visible at a glance, 25% per light\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePass-through charging\u003c\/td\u003e\n\u003ctd\u003eOne cable fills phone and case together overnight\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e360° protection + silicone sides\u003c\/td\u003e\n\u003ctd\u003eCase-grade defense against bumps, scratches, and dust\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNo-chin slim design\u003c\/td\u003e\n\u003ctd\u003eFull access to buttons, ports, and camera\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eShort-circuit\/overcharge protection\u003c\/td\u003e\n\u003ctd\u003eSafe for both phone and case batteries\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e~17.8Wh capacity\u003c\/td\u003e\n\u003ctd\u003eWell under the 100Wh airline carry-on limit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch3\u003eInstallation Guide\u003c\/h3\u003e\n\u003cp\u003e1. Charge the case fully before first use with the original Samsung USB-C charger and cable — all four LEDs lit means 100%. 2. Flex the top edge of the case gently and slide your Galaxy S21 in top-first, seating the USB-C connector at the bottom. 3. Press the corners until the silicone edges sit flush around the frame. 4. The phone begins charging the moment it docks; charging stops automatically when the phone is full. 5. To start a charge manually later, press the power button once; double-press to stop. 6. We recommend pairing with a tempered glass screen protector, since the case protects everything except the screen.\u003c\/p\u003e\n\u003ch3\u003eTroubleshooting\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003ePhone not charging when docked:\u003c\/strong\u003e Check that the USB-C plug is fully seated in the phone's port and press the power button once to wake the case. \u003cstrong\u003eCase won't reach full charge:\u003c\/strong\u003e Use the original Samsung charger and cable — generic chargers commonly cause charging faults with battery cases. \u003cstrong\u003eWireless charging stopped working:\u003c\/strong\u003e That is by design — wireless charging, Samsung Pay, and Android Auto are not supported while the case is on; remove the case to use them. \u003cstrong\u003eComputer won't recognize the phone:\u003c\/strong\u003e Remove the case before syncing — USB data pass-through is not supported. \u003cstrong\u003eCase turns on by itself in a bag:\u003c\/strong\u003e The button can be pressed by tight packing; store the case in a looser pocket or double-press to stop an unwanted charge.\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003e1. Which phone does this fit?\u003c\/strong\u003e The Samsung Galaxy S21 5G with a 6.2-inch screen — only that model. \u003cstrong\u003e2. Which models will NOT fit?\u003c\/strong\u003e The Galaxy S21+ (6.7\"), Galaxy S21 Ultra (6.8\"), and Galaxy S21 FE all have different dimensions and will not fit. No iPhone or other Android model fits either. \u003cstrong\u003e3. How much extra battery do I get?\u003c\/strong\u003e The 4800mAh pack adds roughly 100% — up to 14 hours of talk, 15 hours of filming, or 56 hours of music playback. \u003cstrong\u003e4. Does it charge automatically when my phone runs low?\u003c\/strong\u003e No — you stay in control. Press the power button once to start charging, twice to stop. \u003cstrong\u003e5. Can I charge phone and case at the same time?\u003c\/strong\u003e Yes, pass-through charging fills both with one cable and stops automatically when full. \u003cstrong\u003e6. Does wireless charging work through the case?\u003c\/strong\u003e No — wireless charging is not supported with this case on (0W through-case). Remove the case to use a wireless pad. \u003cstrong\u003e7. What else is unavailable while the case is on?\u003c\/strong\u003e Samsung Pay, Android Auto, Quick Charge, USB-C wired headphones, and PC data sync — remove the case for those. \u003cstrong\u003e8. How do I check the case's remaining power?\u003c\/strong\u003e The 4-light LED gauge shows 25% per light. \u003cstrong\u003e9. Can I fly with it?\u003c\/strong\u003e Yes — at approximately 17.8Wh it is far below the FAA 100Wh carry-on limit. Carry it in the cabin, not checked luggage. \u003cstrong\u003e10. Does it protect my screen?\u003c\/strong\u003e The case protects the body 360° but not the screen — add a tempered glass protector. \u003cstrong\u003e11. What charger should I use?\u003c\/strong\u003e The original Samsung charger and cable; generic chargers can cause the case to malfunction. \u003cstrong\u003e12. Is there drop protection?\u003c\/strong\u003e Reinforced corners and silicone sides absorb everyday bumps and drops; it is protection-grade but not a dedicated MIL-STD rugged case. \u003cstrong\u003e13. Do you offer free shipping?\u003c\/strong\u003e Yes — free shipping across the USA, with delivery typically in under a week. \u003cstrong\u003e14. Is there a discount code?\u003c\/strong\u003e Yes — code \u003cstrong\u003e10OFF\u003c\/strong\u003e saves 10% at checkout. \u003cstrong\u003e15. What is your return policy?\u003c\/strong\u003e To start a return, you can contact us at gorillacasestore@gmail.com. If your return is accepted, we'll send you a return shipping label, as well as instructions on how and where to send your package. Items sent back to us without first requesting a return will not be accepted.\u003c\/p\u003e\n\u003ch3\u003eWhat Owners Are Saying\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003e★★★★★ Derek Holloway, courier driver – Manchester, UK:\u003c\/strong\u003e \"GPS on screen from 8 to 6 used to kill my S21 by lunch. Now I click the button at noon and finish the day with charge to spare. The LED lights are dead useful.\"\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e★★★★★ Priya Raman, ER nurse – Chennai, India:\u003c\/strong\u003e \"Twelve-hour shifts, no time to babysit a charger. The case doubles my battery and the corners have already survived two tile-floor drops. Exactly what I needed.\"\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e★★★★★ Tomás Silva, tour guide – Lisbon, Portugal:\u003c\/strong\u003e \"I translate, navigate, and photograph for groups all day. One cable at night charges both phone and case. My S21 feels new again.\"\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e★★★★★ Hannah Schreiber, geology student – Vienna, Austria:\u003c\/strong\u003e \"Field trips mean ten hours away from any outlet. 4800mAh strapped to the phone beats remembering a power bank every single time.\"\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e★★★★½ Caleb Moore, rideshare driver – Columbus, USA:\u003c\/strong\u003e \"Does what it promises — basically doubles my battery and the grip is great. You give up wireless charging and Samsung Pay while it's on, which costs it half a star, but for all-day driving it's worth the trade.\"\u003c\/p\u003e\n\u003ch3\u003eKeep Reading: Gorilla Cases Guides\u003c\/h3\u003e\n\u003cp\u003eWant to see how modern Samsung protection stacks up? Read our \u003ca href=\"https:\/\/gorillacasestore.com\/blogs\/news\/galaxy-s24-ultra-case-battle-metal-vs-waterproof-vs-wallet-2026\"\u003eGalaxy S24 Ultra case battle: metal vs waterproof vs wallet\u003c\/a\u003e, or check the \u003ca href=\"https:\/\/gorillacasestore.com\/blogs\/news\/best-galaxy-s26-heavy-duty-case-2026-mil-std-810g\"\u003ebest Galaxy S26 heavy duty case of 2026\u003c\/a\u003e for MIL-STD-810G-grade ideas across the Galaxy line.\u003c\/p\u003e\n\u003cp\u003eYour Galaxy S21 has years left in it — give it the battery it deserves. Grab yours with code \u003cstrong\u003e10OFF\u003c\/strong\u003e for 10% off, enjoy free USA shipping with fast delivery, and join the Gorilla Family. We keep you charged and protected.\u003c\/p\u003e","brand":"Gorilla Cases","offers":[{"title":"Black","offer_id":48433189060852,"sku":"1BAT-S21-BLK","price":44.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0569\/5750\/1616\/files\/61hpDEoS3OL._AC_SL1500.jpg?v=1780821410","url":"https:\/\/gorillacasestore.com\/en-de\/products\/galaxy-s21-battery-case-4800mah","provider":"Gorilla Cases","version":"1.0","type":"link"}