How to charge both my NiMH and Lithium batteries?

[Murray Fisher]

July 1st I received the deal from Segway of Oakland where I got the NiMH batteries with my new yellow i180. (Traded in my i167 after 2 years and 3K miles). In the deal I also paid for the Lithium's which will be shipped when available. I am in a quandary as to how to keep both sets of batteries charged up. It appears there are two ways.....ONE: swap out the batteries every month or so......this is not desirable to me at all, as I don't like the idea of physically changing them that often. Screws might get cross threaded or over or under tightened etc. Not a good thing. TWO: the other option would be to buy a separate charger, which I understand is quite expensive..(over $200).
It may be my only alternative though. I only got the NiMH batteries as I intend to be flying with the Segway and cannot fly with the Lithium's so far. Unlike most on here I really don't need the range of the Lithium's, but would use them if I had them. I had the i167 two years and glided with it a little over 3K miles. Does anyone have any suggestions as to the charging. I understand they should be kept charged up regularly and not just "stored" on a shelf.


Murray Fisher

[W9GFO]

It is a problem. The $295 price tag for what amounts to be little more than a power supply is, in my opinion, quite overpriced.

I've offered to trade a pair of good NiMH batteries for a used off board charger but absolutely noone was interested. I try to rotate my packs on a regular basis. I think I have something like six or eight sets between two machines. It's a pain in the a$$ for sure.

Rich H

The Un-Official Segway Battery FAQ
http://www.spinfoot.com/SegwayBatteryFAQ.html

[Murray Fisher]

Yes, that is a terrible price to pay for a charger. I just bought one to carry in the motorhome in case of emergency and it has the works...fully automatic and an ammeter so you can tell just where you stand and it was on sale at Sears for $39.95! What a difference. If you hear of any used ones for sale, let me know!! I am W7NSU, licensed 60 years!!

quote:Originally posted by W9GFO

It is a problem. The $295 price tag for what amounts to be little more than a power supply is, in my opinion, quite overpriced.

I've offered to trade a pair of good NiMH batteries for a used off board charger but absolutely noone was interested. I try to rotate my packs on a regular basis. I think I have something like six or eight sets between two machines. It's a pain in the a$$ for sure.

Rich H

The Un-Official Segway Battery FAQ
http://www.spinfoot.com/SegwayBatteryFAQ.html


Murray Fisher

[Lohja]

Rich H,

You have mail!

Lohja

lohja@cox.net
Of all the things I have lost in my life, I miss my mind the most.

[bystander]

Re: How to charge both my NiMH and Lithium batteries?

I've been thinking about that question too. The $295 plus tax solution seems a little steep for someone with only one HT. After all, I can only ride with one set at a time, so I don't need both sets of packs fast charged.

Although I don't have the second set of batteries yet, I do perceive there may be a bit of red tape (actual availability date, scheduling the upgrade to v14 at a local dealer, etc.) between here and there.

In the meantime, I've been thinking about a "trickle only" charger. Something a pair of battery packs could be plugged into while not being used on the HT.

It seems to me a 40v DC power supply with four current-limited outputs (one for each half-pack) could be utilized. I don't know (yet) what the current limit should be, I would guess 10 to 50 mA.

Perhaps the 40V could be multiplexed to the 4 half-packs. The design would be more complicated due to the multiplexing, but simpler as only one current-limiter would be needed.

40 VDC power supplies are not common however, so a customized, rather than off-the-shelf solution may be required.

Maybe if you had three identical, inexpensive 12 volt wall-wart type chargers, and they were line-isolated by internal transformers, you might be able to connect their outputs in series to make a 36-40 V supply.

Another obstacle to overcome is the battery pack connectors. Can a substitute for the four main power connector pins be found? Is it OK to assume the eight smaller connector pins don't need to be connected during a trickle charge?

Since we're not fast charging, it might be OK to not monitor the pack temperature. If temperature monitoring is desirable for safety reasons, perhaps that can be added with an external temp. probe, although that will bring the cost up a bit.

I've noticed that the trickle charge mode on the HT seems to consist of a 40W (or so) spike ever few seconds, rather than a constant 700mW (or so) draw. It remains to be seen whether a constant trickle is equivalent to the pulsed trickle mode now utilized.

The last worry is whether a homebuilt solution is as safe and effective as the $295 off-board charger. To some, the $250 or so saved might not be worth the "peace of mind" of a manufacturer authorized solution.

It sure would be nice if Segway LLC offered a "trickle only" charger for around $40-$50. But I think they have bigger fish to fry right now.

[kaufmanb]

Rich,
I have a customer that wants to sell and off board charger, let me know if I can help you get it. He actually has 2 that he wants to sell.

Brian Kaufman-Butler
Segway of Cleveland
216-241-6100
www.GoSegway.Net

[orgophile]

Hey Rich,

I would be interested in purchasing one of the off-board chargers if the price is right. Email me with the info please.

Thanks

Roger

[Murray Fisher]

What is the price (if any left!!!)

murrayfw@charter.net

quote:Originally posted by kaufmanb

Rich,
I have a customer that wants to sell and off board charger, let me know if I can help you get it. He actually has 2 that he wants to sell.

Brian Kaufman-Butler
Segway of Cleveland
216-241-6100
www.GoSegway.Net


Murray Fisher

[KSagal]

I could easily be interested as well.

E-mail me if either charger is still available...


Karl Ian Sagal

Each road you travel should be just a bit better for having had you pass.