For a long‑haul LiPo I keep the charge‑rate in the 0.5‑1C range for the bulk phase, then drop it to 0.2‑0.3C for topping. That gives a gentle slope on the curve and keeps the cell temps in the 35‑45 °C band. I also pre‑heat the cells a bit in a warm room before charging; it evens out the chemistry and the charger doesn’t see a sudden spike. If you’re using a smart charger, set a temperature limit at 50 °C and make the charger pause when it hits that point – it keeps the curve flat. Finally, run a quick calibration with a known‑good pack before the shoot; that way the charger’s internal maps line up with reality and you avoid those nasty thermal surges.