{"product_id":"speras-i4-4-slot-battery-charger-18650-fast-charger-21700-battery-charger","title":"SPERAS i4 Charger 4 slot Charger 21700 Charger","description":"\u003cstyle\u003e\n    \/* 🏆 Hero Banner Style (Consistent with template) *\/\n    .speras-hero-banner { background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%); padding: 50px 30px; border-radius: 20px; margin-bottom: 40px; text-align: center; border-bottom: 6px solid #ea580c; box-shadow: 0 10px 25px rgba(0,0,0,0.15); }\n    .speras-hero-banner h1 { font-size: 38px; font-weight: 900; color: #ffffff !important; margin: 0 0 15px 0; line-height: 1.3; }\n    .speras-hero-banner .subtitle { font-size: 18px; max-width: 850px; margin: 0 auto 20px auto; color: #cbd5e1 !important; line-height: 1.7; }\n    \n    \/* Comparison Table *\/\n    .speras-table-wrapper { overflow-x: auto; margin: 40px 0; border-radius: 12px; box-shadow: 0 4px 15px rgba(0,0,0,0.05); border: 1px solid #e2e8f0; }\n    .speras-table { width: 100%; border-collapse: collapse; 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visibility: visible; }\n    #speras-lightbox img { max-width: 90vw; max-height: 90vh; border-radius: 12px; box-shadow: 0 10px 40px rgba(0,0,0,0.5); transform: scale(0.9); transition: transform 0.3s ease; }\n    #speras-lightbox.active img { transform: scale(1); }\n\n    \/* ========================================================= *\/\n    \/* 📱 移动端防重叠与防偏移修复补丁 (终极防线) *\/\n    \/* ========================================================= *\/\n    @media screen and (max-width: 850px) {\n        .speras-pdp-container { padding: 10px !important; overflow: hidden !important; box-sizing: border-box !important; }\n        \n        \/* 强制打散所有 Flex 布局，变为上下单列，清除宽度限制 *\/\n        .speras-pdp-container div[style*=\"display: flex\"] { display: block !important; padding: 15px !important; height: auto !important; }\n        \n        .speras-pdp-container div[style*=\"flex: 1\"] { \n            display: block !important; \n            width: 100% !important; \n            max-width: 100% !important; 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line-height: 1.4 !important; margin-bottom: 15px !important; }\n        .speras-pdp-container h3 { font-size: 20px !important; line-height: 1.5 !important; margin-bottom: 15px !important; }\n        .speras-pdp-container p, .speras-pdp-container li, .speras-pdp-container td { line-height: 1.6 !important; font-size: 16px !important; }\n        \n        \/* 确保手机端图片100%居中，不偏移撑破屏幕 *\/\n        .speras-pdp-container img { max-width: 100% !important; height: auto !important; margin: 0 auto !important; display: block !important; box-sizing: border-box !important; }\n    }\n\u003c\/style\u003e\n\u003cdiv class=\"speras-pdp-container\" style=\"font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; color: #333; line-height: 1.7; max-width: 950px; margin: 0 auto;\"\u003e\n\u003cdiv class=\"speras-hero-banner\"\u003e\n\u003cspan style=\"display: inline-block; background: #ea580c; color: #fff; padding: 6px 18px; border-radius: 30px; font-size: 14px; font-weight: 800; text-transform: uppercase; letter-spacing: 1.5px; margin-bottom: 20px;\"\u003eStreamlined 4-Slot Power\u003c\/span\u003e\n\u003ch1\u003eSPERAS i4 Smart LED 4-Slot Battery Charger\u003c\/h1\u003e\n\u003cp class=\"subtitle\"\u003eMaximum reliability without the complexity. The \u003cstrong style=\"color: #ea580c;\"\u003eSPERAS i4\u003c\/strong\u003e is a rugged, highly efficient 4-bay charger featuring clear LED indicators, up to 2A fast charging in the fourth slot, and automatic intelligent charging modes (CC, CV, dv\/dt) to keep all your Li-ion and Ni-MH batteries performing at their peak.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"text-align: center; margin-bottom: 50px;\"\u003e\u003cimg class=\"speras-zoom\" style=\"display: block; margin: 0 auto; max-width: 500px; width: 100%; height: auto; border-radius: 8px; box-shadow: 0 4px 15px rgba(0,0,0,0.05);\" alt=\"SPERAS i4 4-slot battery charger loaded with various Li-ion batteries including 21700 and 18650, alongside a USB-C cable\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0605\/4549\/9313\/files\/i4-2.jpg?v=1688475542\"\u003e\u003c\/div\u003e\n\u003ch2 style=\"font-size: 28px; font-weight: bold; color: #111; margin-bottom: 20px; text-align: center;\"\u003ei4 vs. D4S: Choose Your 4-Slot Charger\u003c\/h2\u003e\n\u003cp style=\"text-align: center; font-size: 16px; color: #555; max-width: 700px; margin: 0 auto 30px auto;\"\u003eNeed 4 charging slots? Choose between the streamlined, rugged efficiency of the i4 or the premium display feedback of the D4S.\u003c\/p\u003e\n\u003cdiv class=\"speras-table-wrapper\"\u003e\n\u003ctable class=\"speras-table\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eFeature\u003c\/th\u003e\n\u003cth style=\"background-color: #334155;\"\u003ei4 (Streamlined Efficiency)\u003c\/th\u003e\n\u003cth style=\"background-color: #ea580c;\"\u003e\u003cspan style=\"color: rgb(255, 255, 255);\"\u003e\u003ca href=\"https:\/\/sperasflashlight.com\/products\/speras-d4s-4-slot-battery-charger-smart-lcd-charger\" target=\"_blank\" title=\"SPERAS D4S LCD Charger 21700 Charger\" style=\"color: rgb(255, 255, 255);\" rel=\"noopener\"\u003e🔥 D4S (Premium Display)\u003c\/a\u003e\u003c\/span\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDisplay Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd class=\"highlight-standard\"\u003eClear LED Indicator Bars\u003c\/td\u003e\n\u003ctd class=\"highlight-brand\"\u003eHigh-Definition LCD Screen\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCharging Slots\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd class=\"highlight-standard\"\u003e4 Independent Slots\u003c\/td\u003e\n\u003ctd class=\"highlight-brand\"\u003e4 Independent Slots\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003e2A Fast Charging\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd class=\"highlight-standard\"\u003eDedicated 4th Slot\u003c\/td\u003e\n\u003ctd class=\"highlight-brand\"\u003eAuto-Selected by Charger\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBest For\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd class=\"highlight-standard\"\u003eRugged, simple, cost-effective charging\u003c\/td\u003e\n\u003ctd class=\"highlight-brand\"\u003eUsers who want exact voltage\/data readouts\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"margin-bottom: 50px;\"\u003e\n\u003ch2 style=\"font-size: 28px; font-weight: bold; color: #111; border-bottom: 2px solid #eee; padding-bottom: 10px; margin-bottom: 30px; text-align: center;\"\u003eCore Professional Features\u003c\/h2\u003e\n\u003cdiv style=\"display: flex; flex-wrap: wrap; align-items: center; margin-bottom: 40px; background: #fafafa; border-radius: 8px; overflow: hidden; border: 1px solid #f0f0f0;\"\u003e\n\u003cdiv style=\"flex: 1 1 300px; padding: 30px;\"\u003e\n\u003ch3 style=\"font-size: 22px; font-weight: bold; color: #ff4500; margin-top: 0;\"\u003eIndependent Control \u0026amp; 2A Fast Charge\u003c\/h3\u003e\n\u003cp style=\"font-size: 16px; margin-bottom: 0;\"\u003eThe i4 controls each of its 4 slots completely independently. It is widely compatible with Li-ion and Ni-MH\/Ni-Cd batteries (including 21700, 26650, and 18650). Need power fast? The dedicated \u003cstrong\u003efourth slot provides up to 2A rapid charging speed\u003c\/strong\u003e to get your high-capacity cells ready in record time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex: 1 1 300px;\"\u003e\u003cimg class=\"speras-zoom\" style=\"width: 100%; height: 100%; object-fit: cover; display: block;\" alt=\"Top angle view of the SPERAS i4 LED charger powering multiple battery chemistries and sizes independently\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0605\/4549\/9313\/files\/i4-2.jpg?v=1688475542\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; flex-wrap: wrap; align-items: center; margin-bottom: 40px; background: #fafafa; border-radius: 8px; overflow: hidden; flex-direction: row-reverse; border: 1px solid #f0f0f0;\"\u003e\n\u003cdiv style=\"flex: 1 1 300px; padding: 30px;\"\u003e\n\u003ch3 style=\"font-size: 22px; font-weight: bold; color: #ff4500; margin-top: 0;\"\u003eSmart Modes \u0026amp; Ultimate Safety\u003c\/h3\u003e\n\u003cp style=\"font-size: 16px; margin-bottom: 0;\"\u003eBehind the simple LED interface is a highly intelligent core. The i4 automatically selects between 3 charging modes (\u003cstrong\u003eCC, CV, or dv\/dt\u003c\/strong\u003e) for optimal battery health. The chassis features an \u003cstrong\u003eexcellent heat dissipation design\u003c\/strong\u003e with built-in cooling vents, paired with robust reverse polarity and short circuit protection.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex: 1 1 300px;\"\u003e\u003cimg class=\"speras-zoom\" style=\"width: 100%; height: 100%; object-fit: cover; display: block;\" alt=\"Bottom view of the SPERAS i4 battery charger showing cooling vents for heat dissipation and the detailed technical specifications label\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0605\/4549\/9313\/files\/i4-3.jpg?v=1688475560\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"background: #fff; padding: 35px; border-radius: 8px; border-left: 6px solid #ea580c; border-top: 1px solid #eee; border-right: 1px solid #eee; border-bottom: 1px solid #eee; margin-bottom: 40px;\"\u003e\n\u003ch3 style=\"font-size: 22px; font-weight: bold; color: #111; margin-top: 0; margin-bottom: 15px;\"\u003eOver-Discharged Battery Activation\u003c\/h3\u003e\n\u003cp style=\"font-size: 16px; color: #555; line-height: 1.8; margin-bottom: 0;\"\u003eDon't throw away \"dead\" batteries just yet. The SPERAS i4 features an advanced \u003cstrong\u003eLi-ion battery restoration function\u003c\/strong\u003e that can safely activate and revive over-discharged cells. Combined with automatic termination upon charging completion, it ensures your batteries are both recovered and protected from overcharging.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"display: flex; flex-wrap: wrap; gap: 30px; margin-bottom: 50px;\"\u003e\n\u003cdiv style=\"flex: 1 1 300px; background: #f8f9fa; color: #333; padding: 30px; border-radius: 8px; border: 1px solid #eee;\"\u003e\n\u003ch2 style=\"font-size: 24px; font-weight: bold; color: #111; margin-top: 0; margin-bottom: 20px;\"\u003eTechnical Specifications\u003c\/h2\u003e\n\u003cul style=\"font-size: 15px; line-height: 1.8; padding-left: 20px; margin-bottom: 0; color: #444;\"\u003e\n\u003cli style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eUSB Input:\u003c\/strong\u003e 5V\/2A\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eDC Output:\u003c\/strong\u003e DC 4.2V \/ 1A * 2 OR 2A * 1 OR 0.5A * 4\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eCompatible Batteries:\u003c\/strong\u003e 21700, 26650, 18650, 16340, 14500 Li-Ion, Ni-MH\/Ni-Cd, etc.\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eDimensions:\u003c\/strong\u003e 110mm (L) * 48.4mm (W) * 28.9mm (H)\u003c\/li\u003e\n\u003cli style=\"margin-bottom: 10px;\"\u003e\n\u003cstrong\u003eWeight:\u003c\/strong\u003e 107.2g (net weight) \/ 146g (gross weight)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003cdiv style=\"flex: 1 1 300px; background: #fff; padding: 30px; border-radius: 8px; border: 1px solid #e0e0e0; box-shadow: 0 2px 8px rgba(0,0,0,0.02);\"\u003e\n\u003ch3 style=\"font-size: 24px; font-weight: bold; margin-top: 0; margin-bottom: 20px; color: #111;\"\u003e📦 What’s in the Box\u003c\/h3\u003e\n\u003cul style=\"font-size: 15px; line-height: 1.8; color: #555; padding-left: 20px; margin-bottom: 20px;\"\u003e\n\u003cli\u003e1 × SPERAS i4 Battery Charger\u003c\/li\u003e\n\u003cli\u003e1 × Charging Cable\u003c\/li\u003e\n\u003cli\u003e1 × Carrying Pouch\u003c\/li\u003e\n\u003cli\u003e1 × User Manual\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cimg class=\"speras-zoom\" style=\"max-width: 100%; border-radius: 8px; margin-top: 10px;\" alt=\"SPERAS i4 battery charger retail packaging and contents including the unit, wrapped USB-C cable, and user manual\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0605\/4549\/9313\/files\/i4-4.jpg?v=1688475579\"\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003ch2 style=\"font-size: 26px; font-weight: bold; border-bottom: 2px solid #eee; padding-bottom: 10px; margin-bottom: 30px;\"\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cdiv style=\"margin-bottom: 50px;\"\u003e\n\u003cdetails open=\"\" style=\"background: #fff; padding: 15px 20px; margin-bottom: 10px; border-radius: 6px; border: 1px solid #ddd; cursor: pointer; box-shadow: 0 2px 5px rgba(0,0,0,0.02);\"\u003e\n\u003csummary style=\"font-size: 18px; font-weight: bold; color: #222; outline: none;\"\u003eWhat is the main difference between the i4 and the D4S?\u003c\/summary\u003e\n\u003cp style=\"margin-top: 15px; font-size: 16px; color: #555; line-height: 1.6;\"\u003eThe SPERAS i4 is a streamlined, highly reliable model that uses simple LED indicator bars to show charging progress. The D4S is the premium version that features a full LCD screen for exact digital readouts. Both safely charge 4 batteries independently.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails style=\"background: #fff; padding: 15px 20px; margin-bottom: 10px; border-radius: 6px; border: 1px solid #ddd; cursor: pointer; box-shadow: 0 2px 5px rgba(0,0,0,0.02);\"\u003e\n\u003csummary style=\"font-size: 18px; font-weight: bold; color: #222; outline: none;\"\u003eWhich slot should I use for 2A fast charging?\u003c\/summary\u003e\n\u003cp style=\"margin-top: 15px; font-size: 16px; color: #555; line-height: 1.6;\"\u003eOn the SPERAS i4, the \u003cstrong\u003efourth slot\u003c\/strong\u003e (far right) is specifically designed to provide up to 2A of rapid charging current. We recommend placing your highest-capacity batteries (like a 21700 or 26650) in this slot when you need them charged as quickly as possible.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003cdetails style=\"background: #fff; padding: 15px 20px; margin-bottom: 10px; border-radius: 6px; border: 1px solid #ddd; cursor: pointer; box-shadow: 0 2px 5px rgba(0,0,0,0.02);\"\u003e\n\u003csummary style=\"font-size: 18px; font-weight: bold; color: #222; outline: none;\"\u003eWhat do the CC, CV, and dv\/dt charging modes mean?\u003c\/summary\u003e\n\u003cp style=\"margin-top: 15px; font-size: 16px; color: #555; line-height: 1.6;\"\u003eThese are automatic smart charging phases designed to protect your battery. The i4 uses \u003cstrong\u003eCC (Constant Current)\u003c\/strong\u003e to charge quickly when the battery is low, switches to \u003cstrong\u003eCV (Constant Voltage)\u003c\/strong\u003e to safely top it off, and uses \u003cstrong\u003edv\/dt (Delta Voltage)\u003c\/strong\u003e termination for Ni-MH batteries to prevent overcharging.\u003c\/p\u003e\n\u003c\/details\u003e\n\u003c\/div\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n    {\n      \"@context\": \"https:\/\/schema.org\",\n      \"@type\": \"FAQPage\",\n      \"mainEntity\": [{\n        \"@type\": \"Question\",\n        \"name\": \"What is the main difference between the i4 and the D4S?\",\n        \"acceptedAnswer\": {\n          \"@type\": \"Answer\",\n          \"text\": \"The SPERAS i4 is a streamlined, highly reliable model that uses simple LED indicator bars to show charging progress. The D4S is the premium version that features a full LCD screen for exact digital readouts. Both safely charge 4 batteries independently.\"\n        }\n      },{\n        \"@type\": \"Question\",\n        \"name\": \"Which slot should I use for 2A fast charging?\",\n        \"acceptedAnswer\": {\n          \"@type\": \"Answer\",\n          \"text\": \"On the SPERAS i4, the fourth slot (far right) is specifically designed to provide up to 2A of rapid charging current. We recommend placing your highest-capacity batteries (like a 21700 or 26650) in this slot when you need them charged as quickly as possible.\"\n        }\n      },{\n        \"@type\": \"Question\",\n        \"name\": \"What do the CC, CV, and dv\/dt charging modes mean?\",\n        \"acceptedAnswer\": {\n          \"@type\": \"Answer\",\n          \"text\": \"These are automatic smart charging phases designed to protect your battery. The i4 uses CC (Constant Current) to charge quickly when the battery is low, switches to CV (Constant Voltage) to safely top it off, and uses dv\/dt (Delta Voltage) termination for Ni-MH batteries to prevent overcharging.\"\n        }\n      }]\n    }\n\u003c\/script\u003e \u003cdiv id=\"speras-lightbox\"\u003e\u003cimg alt=\"Enlarged view of SPERAS i4 charger\" id=\"speras-lightbox-img\"\u003e\u003c\/div\u003e\n\u003cscript\u003e\n    document.addEventListener(\"DOMContentLoaded\", function() {\n        var lightbox = document.getElementById('speras-lightbox');\n        var lightboxImg = document.getElementById('speras-lightbox-img');\n        var images = document.querySelectorAll('.speras-zoom');\n\n        if (lightbox \u0026\u0026 lightboxImg) {\n            images.forEach(function(img) {\n                img.addEventListener('click', function(e) {\n                    e.preventDefault();\n                    lightboxImg.src = this.src;\n                    lightbox.classList.add('active');\n                    document.body.style.overflow = 'hidden';\n                });\n            });\n\n            lightbox.addEventListener('click', function() {\n                lightbox.classList.remove('active');\n                document.body.style.overflow = '';\n                setTimeout(function() {\n                    lightboxImg.src = '';\n                }, 300);\n            });\n        }\n    });\n\u003c\/script\u003e\n\u003c\/div\u003e","brand":"SPERAS","offers":[{"title":"Default Title","offer_id":42784783335601,"sku":"i4","price":24.26,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0605\/4549\/9313\/files\/i4-1.jpg?v=1688475671","url":"https:\/\/sperasflashlight.com\/products\/speras-i4-4-slot-battery-charger-18650-fast-charger-21700-battery-charger","provider":"Speras Light","version":"1.0","type":"link"}