{"title":"Cell Holders \u0026 Insulation","description":"\u003cp\u003e\u003cspan\u003eDurable cases and holders for organizing and protecting 18650 and 21700 cells.\u003c\/span\u003e\u003c\/p\u003e","products":[{"product_id":"21700-battery-spacer-1x2-cell-holder","title":"21700 Cell Spacer \/ Holder – 1×2 Radiating Grid for Pack Assembly","description":"\u003cdiv style=\"max-width: 900px; margin: 0 auto; line-height: 1.6; font-size: 16px;\"\u003e\n\u003ch1\u003e21700 Battery Spacer – 1×2 Radiating Cell Holder\u003c\/h1\u003e\n\u003cp\u003eDesign professional-grade battery packs with these \u003cstrong\u003e1×2 21700 spacers\u003c\/strong\u003e. Their rigid interlocking design keeps cells evenly spaced, promotes heat dissipation, and adds mechanical strength for welding and assembly.\u003c\/p\u003e\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInterlocking structure:\u003c\/strong\u003e build any grid size or pack shape.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRadiating design:\u003c\/strong\u003e open airflow channels improve cooling.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRigid ABS\/PC plastic:\u003c\/strong\u003e durable and lightweight.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePrecision fit:\u003c\/strong\u003e holds 21700 cells securely for spot welding.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eCell size: \u003cstrong\u003e21700 (Ø21 mm × 70 mm)\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eConfiguration: \u003cstrong\u003e1×2 cell layout\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eMaterial: ABS\/PC (black)\u003c\/li\u003e\n\u003cli\u003eTemperature range: −20 °C – 80 °C typical\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003ePackage Includes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eYour selected quantity of \u003cstrong\u003e1×2 21700 spacers\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eUsage\u003c\/h3\u003e\n\u003cp\u003eIdeal for \u003cem\u003eDIY e-bike, power tool, solar, and robotics battery packs\u003c\/em\u003e. For 18650 cells, see our  18650Spacers.\u003c\/p\u003e\n\u003ch3\u003eNotes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eSpacers only – batteries, nickel strips, and BMS not included.\u003c\/li\u003e\n\u003cli\u003eEnsure proper insulation and cell polarity when assembling packs.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp style=\"margin-top: 16px;\"\u003eQuestions about quantities or layout design? \u003cstrong\u003eMessage RenewSpark\u003c\/strong\u003e for help.\u003c\/p\u003e\n\u003cp style=\"margin-top: 16px;\"\u003e—  \u003cbr\u003eDownload “RenewSpark Tools” on the iOS App Store — the toolbox I use for battery building.\u003cbr\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"RenewSpark","offers":[{"title":"10-Pack","offer_id":47445770272995,"sku":"HD105","price":3.49,"currency_code":"USD","in_stock":false},{"title":"50-Pack","offer_id":47445770305763,"sku":"HD106","price":7.49,"currency_code":"USD","in_stock":false},{"title":"100-Pack","offer_id":47445770338531,"sku":"HD107","price":12.99,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/IMG_2891.jpg?v=1762226003"},{"product_id":"dewalt-20v-18650-battery-cell-holder","title":"DeWalt 20V Battery Cell Holder – 10-Slot 18650 Spacer for Power Tool Battery Rebuilds","description":"\u003cdiv style=\"max-width: 900px; margin: 0 auto; line-height: 1.6; font-size: 16px;\"\u003e\n\u003ch1\u003eDeWalt 20V Battery Cell Holder – 10-Slot 18650 Spacer for Power Tool Battery Rebuilds\u003c\/h1\u003e\n\u003cp\u003eThis precision-molded \u003cstrong\u003e10-slot 18650 cell holder\u003c\/strong\u003e is designed for rebuilding or upgrading \u003cstrong\u003eDeWalt 20V MAX power tool batteries\u003c\/strong\u003e. It securely holds each cell in place to maintain alignment, improve cooling, and prevent movement inside the pack.\u003c\/p\u003e\n\u003ch2\u003e🔧 Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eCompatible with \u003cstrong\u003eDeWalt 20V \/ 18V packs\u003c\/strong\u003e that use 18650 cells\u003c\/li\u003e\n\u003cli\u003eHolds exactly \u003cstrong\u003e10 × 18650 Li-ion cells\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eDurable \u003cstrong\u003eABS plastic\u003c\/strong\u003e construction – heat and impact resistant\u003c\/li\u003e\n\u003cli\u003ePerfect fit for OEM-style DeWalt power tool battery rebuilds\u003c\/li\u003e\n\u003cli\u003eLightweight and easy to install – drop-in replacement for stock holders\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003e🧰 Applications\u003c\/h2\u003e\n\u003cp\u003eIdeal for technicians and DIY builders rebuilding \u003cstrong\u003eDeWalt 20V MAX \/ XR packs\u003c\/strong\u003e or creating custom Li-ion packs.\u003c\/p\u003e\n\u003ch2\u003e📦 Package Includes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1 × 10-slot DeWalt 20V 18650 battery cell holder (top or bottom half)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eNote: Cells, nickel strips, and BMS not included.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e✔️ \u003cstrong\u003eIn stock\u003c\/strong\u003e – ships from Irvine, CA\u003c\/p\u003e\n\u003cp\u003e—  \u003cbr\u003eDownload “RenewSpark Tools” on the iOS App Store — the toolbox I use for battery building.\u003cbr\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"RenewSpark","offers":[{"title":"Default Title","offer_id":47453604413667,"sku":"HD108","price":4.2,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/F8092DCF-2850-4A48-B4E8-EBC63F7ACDE4.jpg?v=1762279313"},{"product_id":"milwaukee-m18-18650-battery-cell-holder","title":"Milwaukee M18 Battery Cell Holder – 10-Slot 18650 Spacer for Power Tool Battery Rebuilds","description":"\u003cdiv style=\"max-width: 900px; margin: 0 auto; line-height: 1.6; font-size: 16px;\"\u003e\n\u003ch1\u003eMilwaukee M18 Battery Cell Holder – 10-Slot 18650 Spacer for Power Tool Battery Rebuilds\u003c\/h1\u003e\n\u003cp\u003eThis durable \u003cstrong\u003e10-slot 18650 cell holder\u003c\/strong\u003e is specifically designed for rebuilding or upgrading \u003cstrong\u003eMilwaukee M18 18V power tool batteries\u003c\/strong\u003e. It keeps all ten cells perfectly aligned and secured inside the pack for a professional-quality rebuild.\u003c\/p\u003e\n\u003ch2\u003e🔧 Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eCompatible with \u003cstrong\u003eMilwaukee M18 \/ 18V packs\u003c\/strong\u003e that use 18650 Li-ion cells\u003c\/li\u003e\n\u003cli\u003eHolds \u003cstrong\u003e10 × 18650 cells\u003c\/strong\u003e (top or bottom half design)\u003c\/li\u003e\n\u003cli\u003eMade from \u003cstrong\u003ehigh-temperature ABS plastic\u003c\/strong\u003e for strength and durability\u003c\/li\u003e\n\u003cli\u003eEnsures uniform cell spacing and excellent vibration resistance\u003c\/li\u003e\n\u003cli\u003ePerfect for technicians, repair shops, and DIY rebuilders\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003e🧰 Applications\u003c\/h2\u003e\n\u003cp\u003eIdeal for rebuilding \u003cstrong\u003eMilwaukee M18 REDLITHIUM\u003c\/strong\u003e batteries or creating custom Li-ion packs using 18650 cells.\u003c\/p\u003e\n\u003ch2\u003e📦 Package Includes\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e1 × 10-slot Milwaukee M18 18650 cell holder (top or bottom half)\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cem\u003eNote: Cells, nickel strips, and BMS are not included.\u003c\/em\u003e\u003c\/p\u003e\n\u003cp\u003e✔️ \u003cstrong\u003eIn stock\u003c\/strong\u003e – ships from Irvine, CA\u003c\/p\u003e\n\u003cp\u003e—  \u003cbr\u003eDownload “RenewSpark Tools” on the iOS App Store — the toolbox I use for battery building.\u003cbr\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"RenewSpark","offers":[{"title":"Default Title","offer_id":47454069981411,"sku":"HD109","price":4.2,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/FullSizeRender_e47087a3-b7d5-46fa-8e68-7d9d1a061bd9.heic?v=1762280493"},{"product_id":"4-cell-18650-battery-storage-case-clear","title":"4-Cell 18650 Battery Storage Case – Clear Plastic Protective Holder","description":"\u003ch2\u003e4-Cell 18650 Battery Storage Case – Clear Plastic Protective Holder\u003c\/h2\u003e\n\n\u003cp\u003e\u003cstrong\u003eStore and protect up to four 18650 lithium-ion cells in a compact clear plastic storage case.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThis reusable battery case helps keep loose 18650 cells organized while protecting the terminals from accidental contact with metal objects, other batteries, or conductive materials during storage and transport.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eBattery cells are not included.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003ch3\u003eProduct Features\u003c\/h3\u003e\n\n\u003cul\u003e\n  \u003cli\u003eHolds up to four 18650 lithium-ion cells\u003c\/li\u003e\n  \u003cli\u003eClear translucent plastic design\u003c\/li\u003e\n  \u003cli\u003eHinged lid with secure closure\u003c\/li\u003e\n  \u003cli\u003eHelps prevent loose cells from contacting metal objects\u003c\/li\u003e\n  \u003cli\u003eProtects cells from dust, scratches, and minor impact\u003c\/li\u003e\n  \u003cli\u003eCompact design for toolboxes, drawers, bags, and workbenches\u003c\/li\u003e\n  \u003cli\u003eReusable and lightweight\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\n\u003cp\u003eDesigned for standard cylindrical 18650 lithium-ion cells.\u003c\/p\u003e\n\n\u003cp\u003eThis case is not designed for larger 21700 cells or batteries with unusually thick protective wraps, added tabs, or external wiring.\u003c\/p\u003e\n\n\u003ch3\u003eWhat Is Included\u003c\/h3\u003e\n\n\u003cul\u003e\n  \u003cli\u003eOne clear plastic 4-cell 18650 storage case\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat Is Not Included\u003c\/h3\u003e\n\n\u003cul\u003e\n  \u003cli\u003e18650 battery cells\u003c\/li\u003e\n  \u003cli\u003eBattery charger\u003c\/li\u003e\n  \u003cli\u003eOther accessories shown for demonstration\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eImportant Safety Information\u003c\/h3\u003e\n\n\u003cp\u003eAlways inspect lithium-ion cells before use. Do not store or use cells with damaged wrapping, dents, corrosion, leakage, excessive heat, or other visible damage.\u003c\/p\u003e\n\n\u003cp\u003eKeep cells away from water, fire, direct sunlight, extreme temperatures, and conductive materials. This case is intended for storage and organization and does not make damaged or unsafe cells suitable for use.\u003c\/p\u003e\n\n\u003ch3\u003eAdditional Parts and Resources\u003c\/h3\u003e\n\n\u003cp\u003eFor additional battery-building parts, battery holders, nickel strips, connectors, BMS boards, and related supplies, visit \u003cstrong\u003eRenewSpark\u003c\/strong\u003e.\u003c\/p\u003e\n\n\u003cp\u003eFor helpful battery tools, calculators, technical information, and additional resources, download the \u003cstrong\u003eRenewSpark Tools app\u003c\/strong\u003e.\u003c\/p\u003e","brand":"RenewSpark","offers":[{"title":"Default Title","offer_id":49406379819235,"sku":"MS104","price":4.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/554AF874-EA5B-4235-82E4-5D8C4C9FB231.png?v=1784044919"},{"product_id":"2x-18650-storage-case-clear","title":"Battery Storage Case for 2x 18650 \/ 18500 \/ 18350 \/ CR123A – Clear Holder Box","description":"\u003cp\u003e\u003cspan\u003eKeep your rechargeable batteries safe, organized, and protected with this durable clear plastic storage case. Designed to fit 2x 18650 lithium-ion cells, it also works with other popular battery sizes such as 18500, 18350, CR123A, and 16340.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003e✅ Features:\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003cspan\u003eHolds 2 rechargeable batteries securely\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eCompatible with 18650, 18500, 18350, CR123A, 16340\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eClear, lightweight, and durable plastic construction\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eSnap-lock closure prevents accidental opening\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eProtects against dust, dirt, and short circuits\u003c\/span\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cspan\u003eCompact size fits easily into a pocket, bag, or toolbox\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003eNote: Batteries are not included. This listing is for the empty case only.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cspan\u003e—  \u003cbr\u003eDownload “RenewSpark Tools” on the iOS App Store — the toolbox I use for battery building.\u003cbr\u003e\u003c\/span\u003e\u003c\/p\u003e","brand":"RenewSpark","offers":[{"title":"Default Title","offer_id":49432070455523,"sku":"MS102","price":2.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/IMG-7666_5385643a-3df3-4c7c-acba-e6aff0db6c13.png?v=1784609894"},{"product_id":"clear-21700-storage-case-2-cell-carry-box","title":"Clear 21700 Storage Case – 2 Cell Carry Box","description":"\u003ch2\u003eClear 21700 Battery Storage Case (2-Cell)\u003c\/h2\u003e\n\u003cp\u003eKeep your high-power 21700 lithium-ion batteries safe and organized with this durable \u003cstrong\u003eclear plastic storage case\u003c\/strong\u003e. Designed to hold exactly \u003cstrong\u003etwo 21700 cells\u003c\/strong\u003e, this pocket-sized case is perfect for tool batteries, DIY projects, vaping mods, flashlights, and RC packs.\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003e✅ Fits 2 x 21700 cells (protected or unprotected)\u003c\/li\u003e\n  \u003cli\u003e✅ Transparent design for easy visibility\u003c\/li\u003e\n  \u003cli\u003e✅ Secure snap-lock lid prevents accidental opening\u003c\/li\u003e\n  \u003cli\u003e✅ Lightweight and portable — fits easily in a pocket or toolbox\u003c\/li\u003e\n  \u003cli\u003e✅ Protects against short-circuits, dust, and physical damage\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cstrong\u003ePerfect for DIY builders, technicians, and hobbyists\u003c\/strong\u003e who want safe storage and transport for their lithium-ion batteries. A must-have accessory for anyone working with 21700 cells.\u003c\/p\u003e\n\n\u003cdiv style=\"border:2px solid #f44336; padding:12px; font-weight:600;\"\u003e\n⚠️ \u003cstrong\u003eSafety Note:\u003c\/strong\u003e Always store batteries in a proper case. Loose batteries can short-circuit if they come in contact with metal objects (keys, coins, tools).\n\u003c\/div\u003e\n—  \nDownload “RenewSpark Tools” on the iOS App Store — the toolbox I use for battery building.\n\n","brand":"RenewSpark","offers":[{"title":"Default Title","offer_id":49432071373027,"sku":"MS103","price":2.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/IMG-7668_1a02b894-3bb7-4f6c-929d-6f812717311b.png?v=1784609937"},{"product_id":"18650-cell-spacer-1x1","title":"18650 Cell Spacer \/ Holder – 1×1 Interlocking Grid for Pack Assembly","description":"\u003cdiv style=\"max-width: 900px; margin: 0 auto; line-height: 1.6; font-size: 16px;\"\u003e\n\u003ch2\u003e18650 Cell Spacer – 1×1 Interlocking Cell Holder\u003c\/h2\u003e\n\u003cp\u003eBuild cleaner, safer packs with these \u003cstrong\u003esnap-together 18650 spacers\u003c\/strong\u003e. The honeycomb design keeps cells uniformly spaced for better \u003cem\u003eairflow, rigidity, and shock isolation\u003c\/em\u003e—ideal for DIY power-tool, e-bike, scooter, and robotics packs.\u003c\/p\u003e\n\u003ch3\u003eWhy builders like these\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInterlocking grid:\u003c\/strong\u003e snaps together in any layout (series\/parallel).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eThermal spacing:\u003c\/strong\u003e promotes heat dissipation between cells.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eRigid \u0026amp; light:\u003c\/strong\u003e molded ABS\/PC; resists vibration and compression.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eClean welding:\u003c\/strong\u003e keeps cells aligned for consistent nickel strip welds.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eSpecs\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eCell size: \u003cstrong\u003e18650 (Ø18 mm × 65 mm)\u003c\/strong\u003e\n\u003c\/li\u003e\n\u003cli\u003eForm factor: \u003cstrong\u003e1×1 single-cell spacer\u003c\/strong\u003e (interlocks to form larger arrays)\u003c\/li\u003e\n\u003cli\u003eMaterial: ABS\/PC (black); working temp: −20 °C to 80 °C (typ.)\u003c\/li\u003e\n\u003cli\u003eMounting: press-fit around cells; add adhesive\/straps as desired\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhat’s included\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eYour chosen pack size of \u003cstrong\u003e1×1 18650 spacers\u003c\/strong\u003e (no cells or nickel included).\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eCompatibility\u003c\/h3\u003e\n\u003cp\u003eFits standard 18650 cylindrical cells. For 21700 cells, use our 21700 series spacers.\u003c\/p\u003e\n\u003ch3\u003eNotes\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eThese are \u003cem\u003espacers\/holders only\u003c\/em\u003e—no cells, nickel, or BMS.\u003c\/li\u003e\n\u003cli\u003eAlways follow proper cell safety and insulation practices.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp style=\"margin-top: 16px;\"\u003eQuestions about pack layouts or quantities? \u003cstrong\u003eMessage RenewSpark\u003c\/strong\u003e and we’ll help you choose.\u003c\/p\u003e\n\u003cp style=\"margin-top: 16px;\"\u003e—  \u003cbr\u003eDownload “RenewSpark Tools” on the iOS App Store — the toolbox I use for pack building.\u003cbr\u003e\u003c\/p\u003e\n\u003c\/div\u003e","brand":"RenewSpark","offers":[{"title":"10-Pack","offer_id":49433790513379,"sku":"HD101","price":2.99,"currency_code":"USD","in_stock":true},{"title":"50-Pack","offer_id":49433790546147,"sku":"HD102","price":5.49,"currency_code":"USD","in_stock":true},{"title":"100-Pack","offer_id":49433790578915,"sku":"HD103","price":7.99,"currency_code":"USD","in_stock":true},{"title":"500-Pack","offer_id":49433790611683,"sku":"HD104","price":36.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/files\/IMG_2890.jpg?v=1762224654"}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0734\/7594\/8771\/collections\/IMG-0737.png?v=1756564952","url":"https:\/\/renewspark.com\/collections\/cell-holders-insulation.oembed","provider":"RenewSpark","version":"1.0","type":"link"}