It's been my experience that the pack will not rebalance if the batteries are at very different states of charge. In fact, your trickle charger will be cooking the "full" batteries ( albeit slowly) while the "low" batteries try to catch up. You might get the pack more in sync by charging until the high batts are full, then discharging the pack a decent percentage, and charging again until the high batts are full.... Repeat half a dozen times and if you are using FLAs, keep your cells watered...
Alternatively, you can use a regular 12v portable charger to individually charge just one battery while the battery is wired into are larger pack. Just put the charging leads on the low batt and it will charge independently. If you monitored the charge used by the half pack, you can roughly balance the low batts before you do your regular re-charge. For example, if you used 15Ah at 24V, and you've got a 25A 12V charger. Then running the 12V charger on each low batt for about 35 minutes will put them very close to the other batts. Then hook up your regular 48v charger and everything should be fine.
But any time that you're hand balancing a battery pack, it's a good idea to check your progress with a voltage meter (VOM) as was suggested before.
Another solution would be to switch your "half banks" some near the middle of your 24V testing and discharge both parts more equally. Personally, I would that,
Good luck with the test, this ain't rocket surgery, but you can commit a fairly expensive mistake, especially with the unattended 48V trickle charger.
I'm looking forward to your results.
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, oak <oak_box@...> wrote:
>
> I know this isn't optimal, but for tomorrow, I need to work with what I've got... Will this work???
>
> So....
>
> If I charge all 4 batteries for the next 2-3 days on a small 48V trickle charger - will they eventually equalize out? (I would expect that they would.)
>
> Longer term (and I think I've already asked this question, and gotten a "yes", but just checking again...) - if I hook up two 12V chargers to two 12V batteries connected in series, is there any problem? I'm assuming the chargers have outputs that are isolated from the input and from ground.
>
> I hope to have some interesting data to post soon!
>
> John
>
| Reply via web post | Reply to sender | Reply to group | Start a New Topic | Messages in this topic (14) |
No comments:
Post a Comment