Battery Vehicle Society

I'm trying to source some of these batteries:

http://www.hobbyking.com/hobbyking/stor ... duct=14617

Apparently they can provide 450A of current for short bursts which suit my application perfectly.

Hobbyking don;t answer their emails! is there a UK or European source?

I've bought loads of LiPos from HK and found them generally pretty good to deal with. There aren't many English speakers there though, plus there's a big time difference, so it can take a day or two to get an answer (you will probably get a reply eventually, depending on the nature of your question, but if it's technical then it's quite likely to be a bit of a garbled reply as the techies are generally non-English speakers, I believe). They are a pretty big operation, with warehouses in Germany, Australia and the US as well as mainland China. They pretty much expect people to just buy from the site, rather than try and ask questions first, as they are very much a cut-price operation, without much in the way of front-office support.

What is it you want to know about these cells?

Jeremy

HI Jeremy I wanted to know which charger to use. What would you recommend? I tried ordering some last night but it got blocked due to a max 3200mAh limit for postage. I cant seem to understand what they have in their German warehouse.

Charging is a bit of a pain, but pretty much any RC Lipo balance charger will work fine. It depends how fast you want to recharge the packs and what size packs you choose to use, as some chargers only have a 5S or 6S upper limit (although some of the top end ones will now charge 10S.

HK wouldn't be able to advise you well, as they won't know your battery pack configuration - this is an oddball use of these packs, not something they or the chargers are designed for.

For example, I use 4off 5S packs in my folding bike. The pack is configured so that it is really a 10S 2P pack, with two pairs of parallel connected (at the cell level) packs wired in series to give me the right configuration. I charge this pack with two 5S capable chargers, but have to split the pack back to two 5S 2P packs because I run both chargers from a common 12V supply.

The chargers you choose to use will depend very much on the topology you opt for when building the battery pack up. There are very few 10S capable chargers about, HK only stock two, this one: http://www.hobbyking.com/hobbyking/stor ... oduct=6609 and this one: http://www.hobbyking.com/hobbyking/stor ... duct=11597

I've not used either, so can't say how good they are. The difference between the two seems to be that the 1010 is 300W and the 3010 is 1000W, so will charge faster. Both will need suitable power supplies (they aren't mains powered, as the RC boys charge in the field from car batteries). You will either need to take the battery apart to charge it in sections, or get enough chargers and power supplies to allow charging with the pack assembled. You'll need to maintain isolation if you go for the multiple charger approach, which means careful choice of isolated power supplies to run the chargers. Either way you need to bring all the battery connectors out so they can be hooked up to the charger - these chargers all balance charge by sensing cell voltage from the multi-pin balance connectors on the battery packs.

Jeremy