Batboard

I have just acquired an XPR7350 which was manufactured in April 2014.

I was assuming that Motorola would now only supply new radios with Lithium Ion batteries...but it came with a NiMH battery!!!

So why does Motorola still bother with NiMH batteries on new radios?

Why does anybody want to use NiMH batteries vs Lithium Ion batteries?

Surely its just a cheap to make a Lithium Ion battery?

Can you still buy a new cell phone which is supplied with a NiMH battery?

The NiMh chemistry is alive and well and replacing NiCd little by little. Li-Ion is often not the best choice. Most of the highlights are covered here.
www.batteryuniversity.com

Thanks.

Why do all new laptops and cellphones now only use lithium batteries rather than NiMH's or Nicads?

Surely any issues with lithium batteries have been resolved over the past 10 years?

I can see it makes sense to still make NiMH batteries for older radios which don't have "tri-chem" chargers but you would think it would be cheaper to just focus on producing lithium batteries for new radios?

Lithium batteries are lighter and smaller which is why cellphones and laptops would use them.

I would assume that Motorola doesn't include lithium batteries because they are more expensive, and they can make more money selling lithium batteries after.

In applications where size and mass(weight) are primary considerations LiIon has all the other chemistries beat hands down for energy density in W/Kg. Where lower energy densities are acceptable, engineers are still using NiMH because it's construction is more rugged(and it's short circuit current is less) than LiIon thus reducing the possibility of dangerous overheating and thermal runaway. In addition, LiIon requires internal circuitry to limit short circuit current to safe levels thus making it more expensive to produce, especially for FM applications.

With the few Li-Ion I've had it appears they don't have the shelf life or the amount of charge/discharge cycles that a NiMh or NiCd are capable of. When I bought them I recall Motorola's warranty was only 12 mos. so they apparently recognize this shortcoming. But if you need the best size/weight Li-Ion might be your best option but there are tradeoffs.

I know lithium batteries can be dangerous but "billions" are being used in cell phones and laptops. I guess only a very small percentage go wrong and the technology has been improved over the last 5 years.

OK on shelf life. I bought a load of (probably lightly) used 9 year old HT1250 slim lithium batteries and there was only 1 faulty one out of around 25 - only cost $7 for the lot. They work great and transform the HT1250 from a bit bulky to a super slim light radio!!!

But once a lithium battery fails it seems to be impossible to revive it - with NiMH or Nicads you can usually zap them and then cycle them to get the capacity up!!

Shelf life? I have a Samsung Rugby 2, but I put it away for 18 months when I got a smart phone, but when my smart phone had problems, I took the Rugby out of storage where it had hibernated for 18 months. I didn't recharge the Lion battery, yet it still showed 3/4 charge after sitting in the phone for 18 months. I actually used the phone for 4 days before finally recharging it. To me, that's amazing. GARY

g8tzl2004 wrote:Surely any issues with lithium batteries have been resolved over the past 10 years?

The issues aren't an issue of technological prowess, they're inherent to the chemistry. Li-ions react very poorly to overcharging and deep discharging, can't sink as much current as a NiMH or NiCd, and are much more sensitive to heat.

g8tzl2004 wrote:I know lithium batteries can be dangerous but "billions" are being used in cell phones and laptops. I guess only a very small percentage go wrong and the technology has been improved over the last 5 years.
!

How many of those get carried into structure fires, mining operations, and hazardous locations? Not many.
Lithium ion batteries don't perform well at high or low temperatures, and in fact, their circuitry will disable them if they get too hot/cold.

for this reason, NiMH has replaced NiCD as a chemistry of choice for those applications. Consumer devices aren't intended for use in these atmospheres, so the comparison of cellphones and laptops is irrelevant.

I guess dangerous applications should be using the expensive "special" Motorola FM NiMH batteries?

I'm still wondering why Motorola bothers with NiMH batteries for "everyday" non-hazardous environments. If lithium batteries are safe enough for billions of cell phones, then presumably they are safe enough for most two way radio applications.

I wonder what percentage of Motorola radios are used in hazardous environments?

Maybe I should be asking why Motorola bothers with "dangerous" lithium batteries as a two way radio is more likely to be used in a hazardous situation than a cell phone so its safer to just focus on NiMH batteries?

"I'm still wondering why Motorola bothers with NiMH batteries for "everyday" non-hazardous environments. If lithium batteries are safe enough for billions of cell phones, then presumably they are safe enough for most two way radio applcations."

Li-Ion is for applications requiring a high degree of power vs. size/weight. It costs more and provides less charge/discharge cycles than Nicd, NiMh. At this point it's not intended to be the new chemistry that
will make others obsolete. NiMh on the other hand is slowly replacing NiCd mainly for environmentally friendly reasons but it also exhibits less of the memory effect of NiCd. For now I'll use my NiCd's, they're the workhorse chemistry.

The following FAA doc is good reading as to why I still use NiMH and Nicad

http://www.faa.gov/about/office_org/hea ... _chart.pdf

while this document is geared towards avionics related incidents, just look at the broad range of consumer products that had battery failures, it's pretty scary.

The sheer number of battery related failures is scary and even though it is a lengthy report to read, take the time and note the number of items that were dropped or bumped of which the lithium batteries failed.

One problem with reports like this are the poor record keeping especially considering a battery that burns up may be impossible to trace back to a legit manufacturer so who knows the quality of the batteries in these incidents.

As you can see some of the batteries in these incidents could have come from questionable sources and these pirate batteries may not have had any protection circuitry built in to them.

mike m wrote:The following FAA doc is good reading as to why I still use NiMH and Nicad

http://www.faa.gov/about/office_org/hea ... _chart.pdf

while this document is geared towards avionics related incidents, just look at the broad range of consumer products that had battery failures, it's pretty scary.

The sheer number of battery related failures is scary and even though it is a lengthy report to read, take the time and note the number of items that were dropped or bumped of which the lithium batteries failed.

One problem with reports like this are the poor record keeping especially considering a battery that burns up may be impossible to trace back to a legit manufacturer so who knows the quality of the batteries in these incidents.

As you can see some of the batteries in these incidents could have come from questionable sources and these pirate batteries may not have had any protection circuitry built in to them.

In line with this the US Postal Service has restrictions on shipping Li-Ion batteries.

I wonder whether the postal restriction on lithium batteries will result in various radios and other devices using a "standard" sized battery so it can be easily sourced locally?

Various Fleabay Chinese radio sellers are now shipping radios by airmail without batteries - the batteries are sent by ship!!!

MTS2000des wrote:

g8tzl2004 wrote:I know lithium batteries can be dangerous but "billions" are being used in cell phones and laptops. I guess only a very small percentage go wrong and the technology has been improved over the last 5 years.
!

How many of those get carried into structure fires, mining operations, and hazardous locations? Not many.
Lithium ion batteries don't perform well at high or low temperatures, and in fact, their circuitry will disable them if they get too hot/cold.

for this reason, NiMH has replaced NiCD as a chemistry of choice for those applications. Consumer devices aren't intended for use in these atmospheres, so the comparison of cellphones and laptops is irrelevant.

All we use are IS/FM Lithium Ion batteries on APXs, they get carried into plenty of structure fires. However, I do know a large department that requires NiCad and is profoundly distraught that /\/\ is phasing them out.