Technical primers, buyer's guides, and cross-reference charts for lead-acid and AGM batteries. AGM vs flooded, cold-weather sizing, BCI group decoding, JIS / DIN cross-reference.
Buyer's guide
AGM batteries handle modern start-stop and high-accessory loads better than flooded; flooded chemistry is still the right call for older standard vehicles. Here's how to tell which one your car needs.
Canadian winter guide
Cold cuts cranking amps in half and drains stored capacity. Here's what CCA rating to look for, what to expect at −30 °C, and how to keep a battery healthy through a Canadian winter.
How to read group sizes
BCI Group 65, 47/H5, 51R — the codes feel arbitrary but every digit means something. Here's the system, and how to read your current battery's case before you order a replacement.
Technical primer
CCA is what starts your engine in winter; RC is what runs your stereo when the engine is off. Here's how to read both numbers and what trade-offs the bigger ones imply.
Cross-reference chart
Japanese makes use JIS group codes (D23, D26, B20); Europeans use DIN (L2, L5, LB3). Here's how those map to the BCI numbers North American dealers stock, with practical examples by make.
More articles publish through Week 6 + Month 2 — the JIS-to-BCI chart is designed to grow as we add per-make pages, and the buyer's guides will get a deeper Canadian-winter expansion alongside the cold-weather corridor coverage in Q4.
