{"product_id":"powertender-4-amp-12v-6v-battery-charger-and-maintainer","title":"PowerTender® 4 Amp 12V\/6V Battery Charger and Maintainer","description":"\u003cp\u003eFour amps. Two voltages. Full Multi-Chemistry support. The PowerTender® 4 Amp 12V\/6V delivers efficient, high-output charging for lead-acid and Lithium batteries at either 6V or 12V — with ISM (Infinite Sequential Monitoring™) ensuring precision at every stage from initial recovery through indefinite float maintenance for both chemistries.\u003c\/p\u003e\u003ch3\u003eThe 4 Amp Advantage\u003c\/h3\u003e\u003cp\u003eAt 4 Amp output, the PowerTender® charges automotive batteries more than three times faster than a 1.25 Amp maintainer during the bulk phase. A fully depleted 60Ah car battery that takes over 48 hours to recover at 1.25 Amp recovers in under 15 hours at 4 Amp — with ISM managing the taper and transition to float automatically. For vehicles that need to be back in service quickly, or batteries too large to recover efficiently at lower outputs, 4 Amp is the practical charging threshold for most passenger vehicles.\u003c\/p\u003e\u003ch3\u003eMulti-Chemistry: Lead-Acid and Lithium\u003c\/h3\u003e\u003cp\u003eA manual chemistry selector delivers the correct ISM charging profile for either lead-acid or Lithium (LiFePO4) batteries. Lithium batteries require higher absorption voltages and a different float protocol than lead-acid — applying the wrong profile damages the battery over time. The PowerTender® 4 Amp eliminates this risk: select the chemistry once, and ISM delivers the correct voltages, tapering, and maintenance protocol for that battery type at either voltage setting.\u003c\/p\u003e\u003ch3\u003eISM: 4-Stage Charging at 4 Amp\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eInitialization\u003c\/strong\u003e — Battery health check and polarity confirmation before current flows at the selected voltage and chemistry\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBulk Charge\u003c\/strong\u003e — Full 4 Amp output restores depleted capacity efficiently at the correct voltage for the selected chemistry\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAbsorption\u003c\/strong\u003e — Current tapers automatically as the battery approaches full charge, eliminating overcharge heat damage for both lead-acid and Lithium\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFloat Maintenance\u003c\/strong\u003e — Delivers the correct maintenance protocol for the selected chemistry indefinitely, 24\/7, without overcharging\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eCompatible battery size range: 14Ah to 100Ah at 6V or 12V. Lead-acid: flooded, AGM, gel cell, and sealed maintenance-free. Lithium: LiFePO4.\u003c\/p\u003e\u003ch3\u003e6V Applications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eClassic and antique automobiles with 6V systems\u003c\/li\u003e\n\u003cli\u003eVintage motorcycles and pre-1960s vehicles\u003c\/li\u003e\n\u003cli\u003eAntique tractors, farm equipment, and machinery\u003c\/li\u003e\n\u003cli\u003eAny 6V lead-acid or Lithium battery from 14Ah to 100Ah\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e12V Applications\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eCars, sedans, and compact SUVs\u003c\/li\u003e\n\u003cli\u003ePickup trucks and full-size SUVs\u003c\/li\u003e\n\u003cli\u003eMotorcycles and touring bikes\u003c\/li\u003e\n\u003cli\u003eATVs, UTVs, and side-by-sides\u003c\/li\u003e\n\u003cli\u003eBoats and marine vessels\u003c\/li\u003e\n\u003cli\u003eLawnmowers and garden tractors\u003c\/li\u003e\n\u003cli\u003eRVs and campers\u003c\/li\u003e\n\u003cli\u003eAny 12V lead-acid or Lithium battery from 14Ah to 100Ah\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eDual Voltage — One Charger for the Entire Garage\u003c\/h3\u003e\u003cp\u003eThe manual 6V\/12V selector delivers full 4 Amp output at either voltage. For garages that maintain both vintage 6V vehicles and modern 12V vehicles — with either lead-acid or Lithium batteries — one PowerTender® 4 Amp replaces multiple separate chargers with one intelligent unit.\u003c\/p\u003e\u003ch3\u003eAutomatic Temperature Compensation\u003c\/h3\u003e\u003cp\u003eCharge voltage adjusts automatically based on ambient temperature at both voltage settings — delivering the correct charge profile in cold winter storage and hot summer conditions without manual adjustment.\u003c\/p\u003e\u003ch3\u003eSafety Features\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpark-proof connection\u003c\/strong\u003e — No current flows until polarity and connection are confirmed correct\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eReverse polarity protection\u003c\/strong\u003e — Automatic shutdown if connections are reversed, protecting Lithium BMS systems and ECUs\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eShort-circuit protection\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003e\u003cstrong\u003eETL and CETL certified\u003c\/strong\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eAfter Charging: Indefinite Float Maintenance\u003c\/h3\u003e\u003cp\u003eAfter the PowerTender® 4 Amp completes bulk and absorption charging, ISM transitions to the correct float maintenance protocol for the selected chemistry automatically. Batteries do not need to be disconnected. Sulfation in lead-acid batteries is prevented entirely through continuous float maintenance. Battery life consistently extends from 2–3 years to 5 years or more.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003e3-Year Limited Warranty | DeLand, Florida Since 1965\u003c\/strong\u003e\u003c\/p\u003e","brand":"Battery Tender®","offers":[{"title":"Default Title","offer_id":52241548247314,"sku":"022-0209-BT-WH","price":104.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1929\/4483\/files\/battery-tender-default-title-4-amp-power-tender-12v-6v-switchable-battery-charger-022-0209-bt-wh-59396462477681.png?v=1777901448","url":"https:\/\/hdwerks.net\/products\/powertender-4-amp-12v-6v-battery-charger-and-maintainer","provider":"HDwerks ","version":"1.0","type":"link"}