I need to charge a 14S LiPo from another 14S LiPo.
The easiest way would be to buy a buck-boost converter with a current limitation, but I couldn't find a single one keeping up with my specs. So I decided to go with two units: first a step-up to slightly over 57.3V (maximum voltage of the LiPos) then a current limited step down. But I also can't find a step-down for these specs neither. I'm, currently at the point where I'm thinking about the simplest way to build an efficient current limiter myself.
An IC that fits pretty much all my needs is the LT3840. It's looking good to me, but almost $9 for a single plain IC of Mouser seems a bit heavy to me. I don't plan to build more than three units but it's still a bit counter intuitive, especially when keeping in mind that I order a few of them for spare.
An alternative would be the L7987 but with its integrated switch I would need three in parallel to handle the power loss.
Please let me know if you know similar ICs or have a completely different idea. Time, or my lack thereof is in fact the main limiting factor over price.