# Lead to Lithium

> Lead to Lithium helps owners convert a 12V lead-acid battery to a 12V LiFePO4 (lithium) battery. It offers a free sizing tool, honest pros and cons, and curated product recommendations with affiliate links for marine, campervan and off-grid solar use. Built by an electrical engineer with 15 years of 12V battery experience.

## Tool
- [Conversion & sizing tool](https://leadtolithium.com/tool): Enter your existing 12V lead-acid battery (by BCI group size or amp-hours) or design from your loads; returns the recommended LiFePO4 pack with a Best Pick plus alternatives.
- [Results (deep-linkable)](https://leadtolithium.com/results): A populated recommendation - Best Pick and tagged alternatives with usable Wh, weight, cycles, warranty and a live-price affiliate link.

## Key guides
- [Lithium vs lead-acid: pros and cons](https://leadtolithium.com/knowledge/pros-cons): Usable capacity, weight, cycle life, charging, cost per cycle - with sources.
- [Marine lithium conversion](https://leadtolithium.com/knowledge/marine): Weight, recharge at anchor, alternator and fusing considerations.
- [Campervan lithium conversion](https://leadtolithium.com/knowledge/campervan): DC-DC charging from the alternator, solar, cold-weather notes.
- [Off-grid solar lithium](https://leadtolithium.com/knowledge/off-grid-solar): Days of autonomy, MPPT setup, deep daily cycling.
- [Cold-weather charging](https://leadtolithium.com/knowledge/cold-weather-charging): The 0 C charge cutoff, self-heating packs, heater pads.
- [Chargers and alternators](https://leadtolithium.com/knowledge/chargers-and-alternators): LFP charge profile (14.2-14.6V bulk, <=13.6V float), DC-DC chargers.

## Key facts
- A 100Ah LiFePO4 gives ~1,024-1,150 Wh usable; a 100Ah lead-acid gives ~510-640 Wh usable (50% depth of discharge).
- Lithium needs roughly half the rated amp-hours of lead-acid for the same usable energy.
- LiFePO4: ~70% lighter, 2,000-5,000 cycles, ~10-year life, charges in 1-2 hours.
- LiFePO4 must not be charged below 0 C without a self-heating pack or heater pad.

## Batteries
- [Browse 12V lithium batteries](https://leadtolithium.com/batteries): Filterable catalogue across brands (LiTime, Power Queen, Renogy, Battle Born, Victron, Epoch) with specs and affiliate links.

## About
- [About & methodology](https://leadtolithium.com/about): Who built this, how the engine works, and the affiliate disclosure.